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Aktivní a neaktivní buňky po k dnech

Je dáno binární pole o velikosti n kde n > 3 . Hodnota true (nebo 1) v poli znamená aktivní a false (nebo 0) znamená neaktivní. Zadanému číslu k je úkolem najít počet aktivních a neaktivních buněk po k dnech. Po každém dni se stav i'té buňky stane aktivním, pokud levá a pravá buňka nejsou stejné, a neaktivní, pokud levá a pravá buňka jsou stejné (obě 0 nebo obě 1). 

Protože před buňkami nejvíce vlevo a za buňkami nejvíce vpravo nejsou žádné buňky, buňky s hodnotou před buňkami nejvíce vlevo a za buňkami nejvíce vpravo jsou vždy považovány za 0 (nebo neaktivní).



Příklady:  

Input : cells[] = {1 0 1 1} k = 2 Output : Active cells = 3 Inactive cells = 1 After 1 day cells[] = {0 0 1 1} After 2 days cells[] = {0 1 1 1} Input : cells[] = {0 1 0 1 0 1 0 1} k = 3 Output: Active Cells = 2  Inactive Cells = 6 Explanation : After 1 day cells[] = {1 0 0 0 0 0 0 0} After 2 days cells[] = {0 1 0 0 0 0 0 0} After 3 days cells[] = {1 0 1 0 0 0 0 0} Input : cells[] = {0 1 1 1 0 1 1 0} k = 4 Output: Active Cells = 3  Inactive Cells = 5

Jediná důležitá věc je ujistit se, že udržujeme kopii daného pole, protože potřebujeme, aby se předchozí hodnoty aktualizovaly pro další den. Níže jsou uvedeny podrobné kroky. 

  1. Nejprve zkopírujeme pole cells[] do pole temp[] a provedeme změny v poli temp[] podle dané podmínky.
  2. Za podmínky je dáno, že pokud je okamžitá levá a pravá buňka i'té buňky buď neaktivní nebo aktivní, stane se i následující den neaktivní, tj.; (buňky[i-1] == 0 a buňky[i+1] == 0) nebo (buňky[i-1] == 1 a buňky[i+1] == 1) pak buňky[i] = 0 lze tyto podmínky použít pomocí XOR buněk[i-1] a buněk[i+1].
  3. Pro 0. index buňky temp[0] = 0^buňky[1] a pro (n-1)'-tý index temp[n-1] = 0^buňky[n-2].
  4. Nyní pro index 1 až n-2 proveďte následující operaci temp[i] = buňky[i-1] ^ buňky[i+1]
  5. Proces opakujte, dokud nebude dokončeno k dní.

Následuje implementace výše uvedených kroků. 



C++
// C++ program to count active and inactive cells after k // days #include   using namespace std; // cells[] - store current status of cells // n - Number of cells // temp[] - to perform intermediate operations // k - number of days // active - count of active cells after k days // inactive - count of active cells after k days void activeAndInactive(bool cells[] int n int k) {  // copy cells[] array into temp [] array  bool temp[n];  for (int i=0; i<n ; i++)  temp[i] = cells[i];  // Iterate for k days  while (k--)  {  // Finding next values for corner cells  temp[0] = 0^cells[1];  temp[n-1] = 0^cells[n-2];  // Compute values of intermediate cells  // If both cells active or inactive then temp[i]=0  // else temp[i] = 1.  for (int i=1; i<=n-2; i++)  temp[i] = cells[i-1] ^ cells[i+1];  // Copy temp[] to cells[] for next iteration  for (int i=0; i<n; i++)  cells[i] = temp[i];  }  // count active and inactive cells  int active = 0 inactive = 0;  for (int i=0; i<n; i++)  (cells[i] == 1)? active++ : inactive++;  printf('Active Cells = %d Inactive Cells = %d'  active inactive); } // Driver program to check the test case int main() {  bool cells[] = {0 1 0 1 0 1 0 1};  int k = 3;  int n = sizeof(cells)/sizeof(cells[0]);  activeAndInactive(cells n k);  return 0; } 
Java
// Java program to count active and  // inactive cells after k days class GFG {   // cells[] - store current status  // of cells n - Number of cells // temp[] - to perform intermediate operations // k - number of days // active - count of active cells after k days // inactive - count of active cells after k days static void activeAndInactive(boolean cells[]   int n int k) {  // copy cells[] array into temp [] array  boolean temp[] = new boolean[n];  for (int i = 0; i < n; i++)  temp[i] = cells[i];  // Iterate for k days  while (k-- > 0) {    // Finding next values for corner cells  temp[0] = false ^ cells[1];  temp[n - 1] = false ^ cells[n - 2];  // Compute values of intermediate cells  // If both cells active or inactive then   // temp[i]=0 else temp[i] = 1.  for (int i = 1; i <= n - 2; i++)  temp[i] = cells[i - 1] ^ cells[i + 1];  // Copy temp[] to cells[] for next iteration  for (int i = 0; i < n; i++)  cells[i] = temp[i];  }  // count active and inactive cells  int active = 0 inactive = 0;  for (int i = 0; i < n; i++)  if (cells[i] == true)  active++;  else  inactive++;  System.out.print('Active Cells = ' + active + ' ' +   'Inactive Cells = ' + inactive); } // Driver code public static void main(String[] args)  {  boolean cells[] = {false true false true  false true false true};  int k = 3;  int n = cells.length;  activeAndInactive(cells n k); } } // This code is contributed by Anant Agarwal. 
Python3
# Python program to count # active and inactive cells after k # days # cells[] - store current # status of cells # n - Number of cells # temp[] - to perform # intermediate operations # k - number of days # active - count of active # cells after k days # inactive - count of active # cells after k days def activeAndInactive(cellsnk): # copy cells[] array into temp [] array temp=[] for i in range(n+1): temp.append(False) for i in range(n): temp[i] = cells[i] # Iterate for k days while (k >0): # Finding next values for corner cells temp[0] = False^cells[1] temp[n-1] = False^cells[n-2] # Compute values of intermediate cells # If both cells active or # inactive then temp[i]=0 # else temp[i] = 1. for i in range(1n-2+1): temp[i] = cells[i-1] ^ cells[i+1] # Copy temp[] to cells[] # for next iteration for i in range(n): cells[i] = temp[i] k-=1 # count active and inactive cells active = 0 inactive = 0; for i in range(n): if(cells[i] == True): active+=1 else: inactive+=1 print('Active Cells ='active'  '  'Inactive Cells =' inactive) # Driver code cells = [False True False True False True False True] k = 3 n =len(cells) activeAndInactive(cells n k) # This code is contributed # by Anant Agarwal. 
C#
// C# program to count active and  // inactive cells after k days using System; class GFG {   // cells[] - store current status  // of cells n - Number of cells // temp[] - to perform intermediate  // operations k - number of days // active - count of active cells  // after k days inactive - count // of active cells after k days static void activeAndInactive(bool []cells   int n int k) {    // copy cells[] array into  // temp [] array  bool []temp = new bool[n];  for (int i = 0; i < n; i++)  temp[i] = cells[i];  // Iterate for k days  while (k-- > 0) {    // Finding next values   // for corner cells  temp[0] = false ^ cells[1];  temp[n - 1] = false ^ cells[n - 2];  // Compute values of intermediate cells  // If both cells active or inactive then   // temp[i]=0 else temp[i] = 1.  for (int i = 1; i <= n - 2; i++)  temp[i] = cells[i - 1] ^ cells[i + 1];  // Copy temp[] to cells[]   // for next iteration  for (int i = 0; i < n; i++)  cells[i] = temp[i];  }  // count active and inactive cells  int active = 0 inactive = 0;  for (int i = 0; i < n; i++)  if (cells[i] == true)  active++;  else  inactive++;  Console.Write('Active Cells = ' + active + ' ' +   'Inactive Cells = ' + inactive); } // Driver code public static void Main()  {  bool []cells = {false true false true  false true false true};  int k = 3;  int n = cells.Length;  activeAndInactive(cells n k); } } // This code is contributed by Nitin Mittal. 
PHP
 // PHP program to count active  // and inactive cells after k // days // cells[] - store current status  // of cells n - Number of cells // temp[] - to perform intermediate  // operations k - number of days // active - count of active cells  // after k days inactive - count of // active cells after k days function activeAndInactive($cells $n $k) { // copy cells[] array into // temp [] array $temp = array(); for ($i = 0; $i < $n ; $i++) $temp[$i] = $cells[$i]; // Iterate for k days while ($k--) { // Finding next values  // for corner cells $temp[0] = 0 ^ $cells[1]; $temp[$n - 1] = 0 ^ $cells[$n - 2]; // Compute values of  // intermediate cells // If both cells active  // or inactive then temp[i]=0 // else temp[i] = 1. for ($i = 1; $i <= $n - 2; $i++) $temp[$i] = $cells[$i - 1] ^ $cells[$i + 1]; // Copy temp[] to cells[]  // for next iteration for ($i = 0; $i < $n; $i++) $cells[$i] = $temp[$i]; } // count active and  // inactive cells $active = 0;$inactive = 0; for ($i = 0; $i < $n; $i++) ($cells[$i] == 1)? $active++ : $inactive++; echo 'Active Cells = ' $active ' Inactive Cells = ' $inactive; } // Driver Code $cells= array(0 1 0 1 0 1 0 1); $k = 3; $n = count($cells); activeAndInactive($cells $n $k); // This code is contributed by anuj_67. ?> 
JavaScript
<script> // javascript program to count active and  // inactive cells after k days  // cells - store current status  // of cells n - Number of cells  // temp - to perform intermediate operations  // k - number of days  // active - count of active cells after k days  // inactive - count of active cells after k days  function activeAndInactive(cells  n  k)   {    // copy cells array into temp array  var temp = Array(n).fill(false);  for (i = 0; i < n; i++)  temp[i] = cells[i];  // Iterate for k days  while (k-- > 0)  {  // Finding next values for corner cells  temp[0] = false ^ cells[1];  temp[n - 1] = false ^ cells[n - 2];  // Compute values of intermediate cells  // If both cells active or inactive then  // temp[i]=0 else temp[i] = 1.  for (i = 1; i <= n - 2; i++)  temp[i] = cells[i - 1] ^ cells[i + 1];  // Copy temp to cells for next iteration  for (i = 0; i < n; i++)  cells[i] = temp[i];  }  // count active and inactive cells  var active = 0 inactive = 0;  for (i = 0; i < n; i++)  if (cells[i] == true)  active++;  else  inactive++;  document.write('Active Cells = ' + active + ' ' + 'Inactive Cells = ' + inactive);  }  // Driver code  var cells = [ false true false true false true false true ];  var k = 3;  var n = cells.length;  activeAndInactive(cells n k); // This code is contributed by Rajput-Ji </script> 

Výstup
Active Cells = 2 Inactive Cells = 6

Časová složitost: O(N*K) kde N je velikost pole a K je počet dní.
Pomocný prostor: O(N)

Tento článek je recenzován týmem geeksforgeeks. Pokud máte lepší přístup k tomuto problému, podělte se.