Třídění je způsob, jak uspořádat prvky seznamu nebo pole v určitém pořadí. Pořadí může být ve vzestupném nebo sestupném pořadí. The číselné a lexikografický (abecední) pořadí je široce používané pořadí.
V této části se naučíme jak třídit pole v Jáva v vzestupně a klesající objednat pomocí seřadit () metoda a bez použití metody sort(). . Spolu s tím se také naučíme jak třídit subarray v Jáva .
Seřadit pole ve vzestupném pořadí
The vzestupně seřadí prvky od nejnižšího po nejvyšší. Je také známý jako přirozený řád nebo číselné pořadí . Třídění můžeme provádět následujícími způsoby:
- Pomocí metody sort().
- Bez použití metody
- Pomocí smyčky for
- Použití metody definované uživatelem
Pomocí metody sort().
v Javě, Pole je třída definovaná vjava.utilbalíček, který poskytuje seřadit () metoda k řazení pole ve vzestupném pořadí. Používá Dual-Pivot Quicksort algoritmus pro třídění. Jeho složitost je O(n log(n)) . Je to a statický metoda, která analyzuje an pole jako parametr a nic nevrací. Můžeme jej vyvolat přímo pomocí názvu třídy. Přijímá pole typu int, float, double, long, char, byte.
Syntax:
public static void sort(int[] a)
Kde A je pole, které má být krátké.
Poznámka: Stejně jako třída Arrays poskytuje třída Collections také metodu sort() k seřazení pole. Ale je mezi nimi rozdíl. Metoda sort() třídy Arrays funguje pro primitivní typ, zatímco metoda sort() třídy Collections funguje pro objekty Collections, jako jsou LinkedList, ArrayList atd.
Pojďme seřadit pole pomocí metody sort() třídy Arrays.
V následujícím programu jsme definovali pole typu integer. Poté jsme vyvolali metodu sort() třídy Arrays a analyzovali pole, které má být tříděno. Pro tisk setříděného pole jsme použili for loop.
SortArrayExample1.java
import java.util.Arrays; public class SortArrayExample1 { public static void main(String[] args) { //defining an array of integer type int [] array = new int [] {90, 23, 5, 109, 12, 22, 67, 34}; //invoking sort() method of the Arrays class Arrays.sort(array); System.out.println('Elements of array sorted in ascending order: '); //prints array using the for loop for (int i = 0; i <array.length; i++) { system.out.println(array[i]); } < pre> <p> <strong>Output:</strong> </p> <pre> Array elements in ascending order: 5 12 22 23 34 67 90 109 </pre> <p>In the above program, we can also use the toSting() method of the Arrays class to print the array, as shown in the following statement. It returns a string representation of the specified array.</p> <pre> System.out.printf(Arrays.toString(array)); </pre> <h3>Without Using the Method</h3> <h3>Using the for Loop</h3> <p>In the following example, we have initialized an array of integer type and sort the array in ascending order.</p> <p> <strong>SortArrayExample2.java</strong> </p> <pre> public class SortArrayExample2 { public static void main(String[] args) { //creating an instance of an array int[] arr = new int[] {78, 34, 1, 3, 90, 34, -1, -4, 6, 55, 20, -65}; System.out.println('Array elements after sorting:'); //sorting logic for (int i = 0; i <arr.length; i++) { for (int j="i" + 1; arr[j]) tmp="arr[i];" arr[i]="arr[j];" arr[j]="tmp;" } prints the sorted element of array system.out.println(arr[i]); < pre> <p> <strong>Output:</strong> </p> <pre> Array elements after sorting: -65 -4 -1 1 3 6 20 34 34 55 78 90 </pre> <h3>Using the User Defined Method</h3> <p>In the following example, we have defined a method named <strong>sortArray()</strong> that contains the logic to sort an array in natural order.</p> <p> <strong>SortArrayExample3.java</strong> </p> <pre> public class SortArrayExample3 { public static void main(String[] args) { int i; //initializing an array int array[] = {12, 45, 1, -1, 0, 4, 56, 23, 89, -21, 56, 27}; System.out.print('Array elements before sorting:
'); for(i = 0; i <array.length; i++) system.out.println(array[i]); invoking user defined method sortarray(array, array.length); system.out.print('array elements after sorting:
'); accessing of the sorted array for(i="0;" i <array.length; { } to sort an in ascending order private static void sortarray(int array[], int n) for (int <n; j="i;" a="array[i];" while ((j> 0) && (array[j-1] > a)) //returns true when both conditions are true { array[j] = array[j-1]; j--; } array[j] = a; } } } </array.length;></pre> <p> <strong>Output:</strong> </p> <pre> Array elements before sorting: 12 45 1 -1 0 4 56 23 89 -21 56 27 Array elements after sorting: -21 -1 0 1 4 12 23 27 45 56 56 89 </pre> <h2>Sort Array in Descending Order</h2> <p>The <strong>descending order</strong> arranges the elements in the highest to lowest order. We can perform sorting in the following ways:</p> <ul> <li>Using the <strong>reverseOrder()</strong> Method</li> <li>Without using the method <ul> <li>Using the <strong>for</strong> Loop</li> <li>Using the <strong>User Defined</strong> Method</li> </ul></li> </ul> <h3>Using the reverseOrder() Method</h3> <p> <a href="/java-collections-class">Java <strong>Collections</strong> class</a> provides the <strong>reverseOrder()</strong> method to sort the array in reverse-lexicographic order. It is a static method, so we can invoke it directly by using the class name. It does not parse any parameter. It returns a <strong>comparator</strong> that imposes the reverse of the natural ordering (ascending order).</p> <p>It means that the array sorts elements in the ascending order by using the sort() method, after that the reverseOrder() method reverses the natural ordering, and we get the sorted array in descending order.</p> <p> <strong>Syntax:</strong> </p> <pre> public static Comparator reverseOrder() </pre> <p>Suppose, a[] is an array to be sort in the descending order. We will use the reverseOrder() method in the following way:</p> <pre> Arrays.sort(a, Collections.reverseOrder()); </pre> <p>Let's sorts an array in the descending order.</p> <p>In the following program, a point to be noticed that we have defined an array as <strong>Integer</strong> . Because the reverseOrder() method does not work for the primitive data type.</p> <p> <strong>SortArrayExample4.java</strong> </p> <pre> import java.util.Arrays; import java.util.Collections; public class SortArrayExample4 { public static void main(String[] args) { Integer [] array = {23, -9, 78, 102, 4, 0, -1, 11, 6, 110, 205}; // sorts array[] in descending order Arrays.sort(array, Collections.reverseOrder()); System.out.println('Array elements in descending order: ' +Arrays.toString(array)); } } </pre> <p> <strong>Output:</strong> </p> <pre> Array elements in descending order: [205, 110, 102, 78, 23, 11, 6, 4, 0, -1, -9] </pre> <p>Let's see another program that sorts array elements in alphabetical order.</p> <p> <strong>SortArrayExample5.java</strong> </p> <pre> import java.util.Arrays; import java.util.Collections; public class SortArrayExample5 { public static void main(String[] args) { String [] strarray = {'Mango', 'Apple', 'Grapes', 'Papaya', 'Pineapple', 'Banana', 'Orange'}; // sorts array[] in descending order Arrays.sort(strarray, Collections.reverseOrder()); System.out.println('Array elements in descending order: ' +Arrays.toString(strarray)); } } </pre> <p> <strong>Output:</strong> </p> <pre> Array elements in descending order: [Papaya, Pineapple, Orange, Mango, Grapes, Banana, Apple] </pre> <h3>Without Using the Method</h3> <h3>Using the for Loop</h3> <p>In the following example, we have initialized an integer array and perform sorting in descending order.</p> <p> <strong>SortArrayExample6.java</strong> </p> <pre> public class SortArrayExample6 { public static void main(String[] args) { int temp; //initializing an array int a[]={12,5,56,-2,32,2,-26,9,43,94,-78}; for (int i = 0; i <a.length; i++) { for (int j="i" + 1; < a.length; j++) if (a[i] a[j]) temp="a[i];" a[i]="a[j];" a[j]="temp;" } system.out.println('array elements in descending order:'); accessing element of the array i="0;" - system.out.println(a[i]); pre> <p> <strong>Output:</strong> </p> <pre> Array elements in descending order: 94 56 43 32 12 9 5 2 -2 -26 -78 </pre> <h3>Using the User Defined Method</h3> <p> <strong>SortArrayExample7.java</strong> </p> <pre> import java.util.Scanner; public class SortArrayExample7 { public static void main(String[] args) { int n, temp; Scanner s = new Scanner(System.in); System.out.print('Enter the number of elements: '); n = s.nextInt(); int a[] = new int[n]; System.out.println('Enter the elements of the array: '); for (int i = 0; i <n; i++) { a[i]="s.nextInt();" } for (int i="0;" < n; j="i" + 1; j++) if (a[i] a[j]) temp="a[i];" a[j]="temp;" system.out.println('array elements in descending order:'); n - system.out.println(a[i]); system.out.print(a[n 1]); pre> <p> <strong>Output:</strong> </p> <pre> Enter the number of elements: 7 Enter the elements of the array: 12 5 56 -2 32 2 -26 Array elements in descending order: 56 32 12 5 2 -2 -26 </pre> <h2>How to Sort Subarray</h2> <p>An array derived from the array is known as <strong>subarray</strong> . Suppose, <strong>a[]</strong> is an array having the elements [12, 90, 34, 2, 45, 3, 22, 18, 5, 78] and we want to sort array elements from 34 to 18. It will sort the subarray <strong>[34, 2, 45, 3, 22, 18]</strong> and keep the other elements as it is.</p> <p>To sort the subarray, the Arrays class provides the static method named <strong>sort()</strong> . It sorts the specified range of the array into ascending order. We can also sort the array of type <strong>long, double, float, char, byte,</strong> etc.</p> <p> <strong>Syntax:</strong> </p> <pre> public static void sort(int[] a, int fromIndex, int toIndex) </pre> <p>The method parses the following three parameters:</p> <ul> <tr><td>a:</td> An array to be sort. </tr><tr><td>fromIndex:</td> The index of the first element of the subarray. It participates in the sorting. </tr><tr><td>toIndex:</td> The index of the last element of the subarray. It does not participate in the sorting. </tr></ul> <p>If formIndex is equal to the toIndex, the range to be sorted is empty. It throws IllegalArgumentException if <strong>fomIndex is greater than toIndex</strong> . It also throws ArrayIndexOutOfBoundsException if <strong>fromIndex a.length</strong> .</p> <p>Let's sort a subarray through a Java program.</p> <p> <strong>SortSubarrayExample.java</strong> </p> <pre> import java.util.Arrays; public class SortSubarrayExample { public static void main(String[] args) { //defining an array int[] a = {12, 90, 34, 2, 45, 3, 22, 18, 5, 78}; // sorts subarray form index 2 to 7 Arrays.sort(a, 2, 7); //prints array using the for loop for (int i = 0; i <a.length; i++) { system.out.println(a[i]); } < pre> <p> <strong>Output:</strong> </p> <pre> Sorted Subarray: 12 90 2 3 22 34 45 18 5 78 </pre> <hr></a.length;></pre></n;></pre></a.length;></pre></arr.length;></pre></array.length;> Ve výše uvedeném programu můžeme k vytištění pole také použít metodu toSting() třídy Arrays, jak ukazuje následující příkaz. Vrátí řetězcovou reprezentaci zadaného pole.
zásobník v ds
System.out.printf(Arrays.toString(array));
Bez použití metody
Pomocí smyčky for
V následujícím příkladu jsme inicializovali pole typu integer a seřadili pole ve vzestupném pořadí.
SortArrayExample2.java
public class SortArrayExample2 { public static void main(String[] args) { //creating an instance of an array int[] arr = new int[] {78, 34, 1, 3, 90, 34, -1, -4, 6, 55, 20, -65}; System.out.println('Array elements after sorting:'); //sorting logic for (int i = 0; i <arr.length; i++) { for (int j="i" + 1; arr[j]) tmp="arr[i];" arr[i]="arr[j];" arr[j]="tmp;" } prints the sorted element of array system.out.println(arr[i]); < pre> <p> <strong>Output:</strong> </p> <pre> Array elements after sorting: -65 -4 -1 1 3 6 20 34 34 55 78 90 </pre> <h3>Using the User Defined Method</h3> <p>In the following example, we have defined a method named <strong>sortArray()</strong> that contains the logic to sort an array in natural order.</p> <p> <strong>SortArrayExample3.java</strong> </p> <pre> public class SortArrayExample3 { public static void main(String[] args) { int i; //initializing an array int array[] = {12, 45, 1, -1, 0, 4, 56, 23, 89, -21, 56, 27}; System.out.print('Array elements before sorting:
'); for(i = 0; i <array.length; i++) system.out.println(array[i]); invoking user defined method sortarray(array, array.length); system.out.print(\'array elements after sorting:
\'); accessing of the sorted array for(i="0;" i <array.length; { } to sort an in ascending order private static void sortarray(int array[], int n) for (int <n; j="i;" a="array[i];" while ((j> 0) && (array[j-1] > a)) //returns true when both conditions are true { array[j] = array[j-1]; j--; } array[j] = a; } } } </array.length;></pre> <p> <strong>Output:</strong> </p> <pre> Array elements before sorting: 12 45 1 -1 0 4 56 23 89 -21 56 27 Array elements after sorting: -21 -1 0 1 4 12 23 27 45 56 56 89 </pre> <h2>Sort Array in Descending Order</h2> <p>The <strong>descending order</strong> arranges the elements in the highest to lowest order. We can perform sorting in the following ways:</p> <ul> <li>Using the <strong>reverseOrder()</strong> Method</li> <li>Without using the method <ul> <li>Using the <strong>for</strong> Loop</li> <li>Using the <strong>User Defined</strong> Method</li> </ul></li> </ul> <h3>Using the reverseOrder() Method</h3> <p> <a href="/java-collections-class">Java <strong>Collections</strong> class</a> provides the <strong>reverseOrder()</strong> method to sort the array in reverse-lexicographic order. It is a static method, so we can invoke it directly by using the class name. It does not parse any parameter. It returns a <strong>comparator</strong> that imposes the reverse of the natural ordering (ascending order).</p> <p>It means that the array sorts elements in the ascending order by using the sort() method, after that the reverseOrder() method reverses the natural ordering, and we get the sorted array in descending order.</p> <p> <strong>Syntax:</strong> </p> <pre> public static Comparator reverseOrder() </pre> <p>Suppose, a[] is an array to be sort in the descending order. We will use the reverseOrder() method in the following way:</p> <pre> Arrays.sort(a, Collections.reverseOrder()); </pre> <p>Let's sorts an array in the descending order.</p> <p>In the following program, a point to be noticed that we have defined an array as <strong>Integer</strong> . Because the reverseOrder() method does not work for the primitive data type.</p> <p> <strong>SortArrayExample4.java</strong> </p> <pre> import java.util.Arrays; import java.util.Collections; public class SortArrayExample4 { public static void main(String[] args) { Integer [] array = {23, -9, 78, 102, 4, 0, -1, 11, 6, 110, 205}; // sorts array[] in descending order Arrays.sort(array, Collections.reverseOrder()); System.out.println('Array elements in descending order: ' +Arrays.toString(array)); } } </pre> <p> <strong>Output:</strong> </p> <pre> Array elements in descending order: [205, 110, 102, 78, 23, 11, 6, 4, 0, -1, -9] </pre> <p>Let's see another program that sorts array elements in alphabetical order.</p> <p> <strong>SortArrayExample5.java</strong> </p> <pre> import java.util.Arrays; import java.util.Collections; public class SortArrayExample5 { public static void main(String[] args) { String [] strarray = {'Mango', 'Apple', 'Grapes', 'Papaya', 'Pineapple', 'Banana', 'Orange'}; // sorts array[] in descending order Arrays.sort(strarray, Collections.reverseOrder()); System.out.println('Array elements in descending order: ' +Arrays.toString(strarray)); } } </pre> <p> <strong>Output:</strong> </p> <pre> Array elements in descending order: [Papaya, Pineapple, Orange, Mango, Grapes, Banana, Apple] </pre> <h3>Without Using the Method</h3> <h3>Using the for Loop</h3> <p>In the following example, we have initialized an integer array and perform sorting in descending order.</p> <p> <strong>SortArrayExample6.java</strong> </p> <pre> public class SortArrayExample6 { public static void main(String[] args) { int temp; //initializing an array int a[]={12,5,56,-2,32,2,-26,9,43,94,-78}; for (int i = 0; i <a.length; i++) { for (int j="i" + 1; < a.length; j++) if (a[i] a[j]) temp="a[i];" a[i]="a[j];" a[j]="temp;" } system.out.println(\'array elements in descending order:\'); accessing element of the array i="0;" - system.out.println(a[i]); pre> <p> <strong>Output:</strong> </p> <pre> Array elements in descending order: 94 56 43 32 12 9 5 2 -2 -26 -78 </pre> <h3>Using the User Defined Method</h3> <p> <strong>SortArrayExample7.java</strong> </p> <pre> import java.util.Scanner; public class SortArrayExample7 { public static void main(String[] args) { int n, temp; Scanner s = new Scanner(System.in); System.out.print('Enter the number of elements: '); n = s.nextInt(); int a[] = new int[n]; System.out.println('Enter the elements of the array: '); for (int i = 0; i <n; i++) { a[i]="s.nextInt();" } for (int i="0;" < n; j="i" + 1; j++) if (a[i] a[j]) temp="a[i];" a[j]="temp;" system.out.println(\'array elements in descending order:\'); n - system.out.println(a[i]); system.out.print(a[n 1]); pre> <p> <strong>Output:</strong> </p> <pre> Enter the number of elements: 7 Enter the elements of the array: 12 5 56 -2 32 2 -26 Array elements in descending order: 56 32 12 5 2 -2 -26 </pre> <h2>How to Sort Subarray</h2> <p>An array derived from the array is known as <strong>subarray</strong> . Suppose, <strong>a[]</strong> is an array having the elements [12, 90, 34, 2, 45, 3, 22, 18, 5, 78] and we want to sort array elements from 34 to 18. It will sort the subarray <strong>[34, 2, 45, 3, 22, 18]</strong> and keep the other elements as it is.</p> <p>To sort the subarray, the Arrays class provides the static method named <strong>sort()</strong> . It sorts the specified range of the array into ascending order. We can also sort the array of type <strong>long, double, float, char, byte,</strong> etc.</p> <p> <strong>Syntax:</strong> </p> <pre> public static void sort(int[] a, int fromIndex, int toIndex) </pre> <p>The method parses the following three parameters:</p> <ul> <tr><td>a:</td> An array to be sort. </tr><tr><td>fromIndex:</td> The index of the first element of the subarray. It participates in the sorting. </tr><tr><td>toIndex:</td> The index of the last element of the subarray. It does not participate in the sorting. </tr></ul> <p>If formIndex is equal to the toIndex, the range to be sorted is empty. It throws IllegalArgumentException if <strong>fomIndex is greater than toIndex</strong> . It also throws ArrayIndexOutOfBoundsException if <strong>fromIndex a.length</strong> .</p> <p>Let's sort a subarray through a Java program.</p> <p> <strong>SortSubarrayExample.java</strong> </p> <pre> import java.util.Arrays; public class SortSubarrayExample { public static void main(String[] args) { //defining an array int[] a = {12, 90, 34, 2, 45, 3, 22, 18, 5, 78}; // sorts subarray form index 2 to 7 Arrays.sort(a, 2, 7); //prints array using the for loop for (int i = 0; i <a.length; i++) { system.out.println(a[i]); } < pre> <p> <strong>Output:</strong> </p> <pre> Sorted Subarray: 12 90 2 3 22 34 45 18 5 78 </pre> <hr></a.length;></pre></n;></pre></a.length;></pre></arr.length;> Použití metody definované uživatelem
V následujícím příkladu jsme definovali metodu s názvem sortArray() který obsahuje logiku pro řazení pole v přirozeném pořadí.
SortArrayExample3.java
public class SortArrayExample3 { public static void main(String[] args) { int i; //initializing an array int array[] = {12, 45, 1, -1, 0, 4, 56, 23, 89, -21, 56, 27}; System.out.print('Array elements before sorting:
'); for(i = 0; i <array.length; i++) system.out.println(array[i]); invoking user defined method sortarray(array, array.length); system.out.print(\'array elements after sorting:
\'); accessing of the sorted array for(i="0;" i <array.length; { } to sort an in ascending order private static void sortarray(int array[], int n) for (int <n; j="i;" a="array[i];" while ((j> 0) && (array[j-1] > a)) //returns true when both conditions are true { array[j] = array[j-1]; j--; } array[j] = a; } } } </array.length;> Výstup:
Array elements before sorting: 12 45 1 -1 0 4 56 23 89 -21 56 27 Array elements after sorting: -21 -1 0 1 4 12 23 27 45 56 56 89
Seřadit pole v sestupném pořadí
The sestupné pořadí uspořádá prvky od nejvyššího po nejnižší. Třídění můžeme provádět následujícími způsoby:
- Za použití obrácené pořadí() Metoda
- Bez použití metody
- Za použití pro Smyčka
- Za použití Definováno uživatelem Metoda
Použití metody reverseOrder().
Jáva Sbírky třída poskytuje obrácené pořadí() metoda k řazení pole v obráceném lexikografickém pořadí. Je to statická metoda, takže ji můžeme vyvolat přímo pomocí názvu třídy. Neanalyzuje žádný parametr. Vrací a srovnávač který ukládá opak přirozeného uspořádání (vzestupné pořadí).
To znamená, že pole třídí prvky ve vzestupném pořadí pomocí metody sort(), poté metoda reverseOrder() obrátí přirozené řazení a dostaneme seřazené pole v sestupném pořadí.
Syntax:
public static Comparator reverseOrder()
Předpokládejme, že a[] je pole, které se má seřadit v sestupném pořadí. Metodu reverseOrder() použijeme následujícím způsobem:
Arrays.sort(a, Collections.reverseOrder());
Seřaďme pole v sestupném pořadí.
V následujícím programu je třeba poznamenat, že jsme definovali pole jako Celé číslo . Protože metoda reverseOrder() nefunguje pro primitivní datový typ.
string.format java
SortArrayExample4.java
import java.util.Arrays; import java.util.Collections; public class SortArrayExample4 { public static void main(String[] args) { Integer [] array = {23, -9, 78, 102, 4, 0, -1, 11, 6, 110, 205}; // sorts array[] in descending order Arrays.sort(array, Collections.reverseOrder()); System.out.println('Array elements in descending order: ' +Arrays.toString(array)); } } Výstup:
Array elements in descending order: [205, 110, 102, 78, 23, 11, 6, 4, 0, -1, -9]
Podívejme se na další program, který třídí prvky pole v abecedním pořadí.
SortArrayExample5.java
import java.util.Arrays; import java.util.Collections; public class SortArrayExample5 { public static void main(String[] args) { String [] strarray = {'Mango', 'Apple', 'Grapes', 'Papaya', 'Pineapple', 'Banana', 'Orange'}; // sorts array[] in descending order Arrays.sort(strarray, Collections.reverseOrder()); System.out.println('Array elements in descending order: ' +Arrays.toString(strarray)); } } Výstup:
Array elements in descending order: [Papaya, Pineapple, Orange, Mango, Grapes, Banana, Apple]
Bez použití metody
Pomocí smyčky for
V následujícím příkladu jsme inicializovali celočíselné pole a provedli řazení v sestupném pořadí.
SortArrayExample6.java
public class SortArrayExample6 { public static void main(String[] args) { int temp; //initializing an array int a[]={12,5,56,-2,32,2,-26,9,43,94,-78}; for (int i = 0; i <a.length; i++) { for (int j="i" + 1; < a.length; j++) if (a[i] a[j]) temp="a[i];" a[i]="a[j];" a[j]="temp;" } system.out.println(\'array elements in descending order:\'); accessing element of the array i="0;" - system.out.println(a[i]); pre> <p> <strong>Output:</strong> </p> <pre> Array elements in descending order: 94 56 43 32 12 9 5 2 -2 -26 -78 </pre> <h3>Using the User Defined Method</h3> <p> <strong>SortArrayExample7.java</strong> </p> <pre> import java.util.Scanner; public class SortArrayExample7 { public static void main(String[] args) { int n, temp; Scanner s = new Scanner(System.in); System.out.print('Enter the number of elements: '); n = s.nextInt(); int a[] = new int[n]; System.out.println('Enter the elements of the array: '); for (int i = 0; i <n; i++) { a[i]="s.nextInt();" } for (int i="0;" < n; j="i" + 1; j++) if (a[i] a[j]) temp="a[i];" a[j]="temp;" system.out.println(\'array elements in descending order:\'); n - system.out.println(a[i]); system.out.print(a[n 1]); pre> <p> <strong>Output:</strong> </p> <pre> Enter the number of elements: 7 Enter the elements of the array: 12 5 56 -2 32 2 -26 Array elements in descending order: 56 32 12 5 2 -2 -26 </pre> <h2>How to Sort Subarray</h2> <p>An array derived from the array is known as <strong>subarray</strong> . Suppose, <strong>a[]</strong> is an array having the elements [12, 90, 34, 2, 45, 3, 22, 18, 5, 78] and we want to sort array elements from 34 to 18. It will sort the subarray <strong>[34, 2, 45, 3, 22, 18]</strong> and keep the other elements as it is.</p> <p>To sort the subarray, the Arrays class provides the static method named <strong>sort()</strong> . It sorts the specified range of the array into ascending order. We can also sort the array of type <strong>long, double, float, char, byte,</strong> etc.</p> <p> <strong>Syntax:</strong> </p> <pre> public static void sort(int[] a, int fromIndex, int toIndex) </pre> <p>The method parses the following three parameters:</p> <ul> <tr><td>a:</td> An array to be sort. </tr><tr><td>fromIndex:</td> The index of the first element of the subarray. It participates in the sorting. </tr><tr><td>toIndex:</td> The index of the last element of the subarray. It does not participate in the sorting. </tr></ul> <p>If formIndex is equal to the toIndex, the range to be sorted is empty. It throws IllegalArgumentException if <strong>fomIndex is greater than toIndex</strong> . It also throws ArrayIndexOutOfBoundsException if <strong>fromIndex a.length</strong> .</p> <p>Let's sort a subarray through a Java program.</p> <p> <strong>SortSubarrayExample.java</strong> </p> <pre> import java.util.Arrays; public class SortSubarrayExample { public static void main(String[] args) { //defining an array int[] a = {12, 90, 34, 2, 45, 3, 22, 18, 5, 78}; // sorts subarray form index 2 to 7 Arrays.sort(a, 2, 7); //prints array using the for loop for (int i = 0; i <a.length; i++) { system.out.println(a[i]); } < pre> <p> <strong>Output:</strong> </p> <pre> Sorted Subarray: 12 90 2 3 22 34 45 18 5 78 </pre> <hr></a.length;></pre></n;></pre></a.length;> Použití metody definované uživatelem
SortArrayExample7.java
import java.util.Scanner; public class SortArrayExample7 { public static void main(String[] args) { int n, temp; Scanner s = new Scanner(System.in); System.out.print('Enter the number of elements: '); n = s.nextInt(); int a[] = new int[n]; System.out.println('Enter the elements of the array: '); for (int i = 0; i <n; i++) { a[i]="s.nextInt();" } for (int i="0;" < n; j="i" + 1; j++) if (a[i] a[j]) temp="a[i];" a[j]="temp;" system.out.println(\'array elements in descending order:\'); n - system.out.println(a[i]); system.out.print(a[n 1]); pre> <p> <strong>Output:</strong> </p> <pre> Enter the number of elements: 7 Enter the elements of the array: 12 5 56 -2 32 2 -26 Array elements in descending order: 56 32 12 5 2 -2 -26 </pre> <h2>How to Sort Subarray</h2> <p>An array derived from the array is known as <strong>subarray</strong> . Suppose, <strong>a[]</strong> is an array having the elements [12, 90, 34, 2, 45, 3, 22, 18, 5, 78] and we want to sort array elements from 34 to 18. It will sort the subarray <strong>[34, 2, 45, 3, 22, 18]</strong> and keep the other elements as it is.</p> <p>To sort the subarray, the Arrays class provides the static method named <strong>sort()</strong> . It sorts the specified range of the array into ascending order. We can also sort the array of type <strong>long, double, float, char, byte,</strong> etc.</p> <p> <strong>Syntax:</strong> </p> <pre> public static void sort(int[] a, int fromIndex, int toIndex) </pre> <p>The method parses the following three parameters:</p> <ul> <tr><td>a:</td> An array to be sort. </tr><tr><td>fromIndex:</td> The index of the first element of the subarray. It participates in the sorting. </tr><tr><td>toIndex:</td> The index of the last element of the subarray. It does not participate in the sorting. </tr></ul> <p>If formIndex is equal to the toIndex, the range to be sorted is empty. It throws IllegalArgumentException if <strong>fomIndex is greater than toIndex</strong> . It also throws ArrayIndexOutOfBoundsException if <strong>fromIndex a.length</strong> .</p> <p>Let's sort a subarray through a Java program.</p> <p> <strong>SortSubarrayExample.java</strong> </p> <pre> import java.util.Arrays; public class SortSubarrayExample { public static void main(String[] args) { //defining an array int[] a = {12, 90, 34, 2, 45, 3, 22, 18, 5, 78}; // sorts subarray form index 2 to 7 Arrays.sort(a, 2, 7); //prints array using the for loop for (int i = 0; i <a.length; i++) { system.out.println(a[i]); } < pre> <p> <strong>Output:</strong> </p> <pre> Sorted Subarray: 12 90 2 3 22 34 45 18 5 78 </pre> <hr></a.length;></pre></n;> Jak třídit Subarray
Pole odvozené z pole je známé jako subarray . Předpokládat, A[] je pole s prvky [12, 90, 34, 2, 45, 3, 22, 18, 5, 78] a my chceme seřadit prvky pole od 34 do 18. Seřadí podpole [34, 2, 45, 3, 22, 18] a ostatní prvky ponechat tak, jak jsou.
Chcete-li třídit podpole, třída Arrays poskytuje statickou metodu s názvem seřadit () . Seřadí zadaný rozsah pole ve vzestupném pořadí. Můžeme také třídit pole typu long, double, float, char, byte, atd.
Syntax:
public static void sort(int[] a, int fromIndex, int toIndex)
Metoda analyzuje následující tři parametry:
Pokud je formIndex roven toIndex, je rozsah, který se má seřadit, prázdný. Vyhodí IllegalArgumentException if formIndex je větší než toIndex . Vyhodí také ArrayIndexOutOfBoundsException if z Index a.délka .
Seřaďme podpole pomocí programu Java.
SortSubarrayExample.java
import java.util.Arrays; public class SortSubarrayExample { public static void main(String[] args) { //defining an array int[] a = {12, 90, 34, 2, 45, 3, 22, 18, 5, 78}; // sorts subarray form index 2 to 7 Arrays.sort(a, 2, 7); //prints array using the for loop for (int i = 0; i <a.length; i++) { system.out.println(a[i]); } < pre> <p> <strong>Output:</strong> </p> <pre> Sorted Subarray: 12 90 2 3 22 34 45 18 5 78 </pre> <hr></a.length;>