La substring más larga de 0 en una string binaria que se repite K veces

Dada la string binaria S de tamaño N y un número K . La tarea es encontrar la substring más larga de 0 en la string que se forma repitiendo K veces la string dada. 
Ejemplos: 
 

Entrada: S = «100001», K = 3 
Salida: 4 
Después de repetir la string dada 3 veces, la string se convierte en 100001100001100001. 
La substring más larga de 0 es 4 
Entrada: S = «010001000», K = 4 
Salida: 4

Acercarse: 
 

1. Si K es uno , encuentre la substring más larga de 0 en una string usando bucles simples
2. Si K es mayor que uno , agregue una string dada al final de la string. Luego, la string se convierte en S + S y la longitud será 2 * N y encuentre la substring más larga de 0 en una string usando bucles simples 
   • Si la substring más larga es 2*N, nuestra respuesta será K*N
   • De lo contrario, será nuestra respuesta requerida.

A continuación se muestra la implementación del enfoque anterior: 
 

// C++ program to find the find the Longest continuous
// sequence of '0' after repeating Given string K time
#include <bits/stdc++.h>
using namespace std;
 
// Function to find the longest substring of 0's
int longest_substring(string s, int k)
{
    // To store size of the string
    int n = s.size();
     
    if(k>1)
    {
        s += s;
        n *= 2;
    }   
     
    // To store the required answer
    int ans = 0;
     
    // Find the longest substring of 0's
    int i = 0;
    while (i < n)
    {
        int x = 0;
         
        // Run a loop upto s[i] is zero
        while (s[i] == '0' && i < n)
            x++, i++;
        ans = max(ans, x);
        i++;
    }
     
    // Check the conditions
    if(k==1 or ans!=n)
        return ans;
         
    else
        return (ans/2)*k;
}
 
// Driver code
int main()
{
    string s = "010001000";
     
    int k = 4;
     
    // Function call
    cout << longest_substring(s, k);
     
    return 0;
}

// Java program to find the Longest continuous
// sequence of '0' after repeating Given string K time
class GFG
{
 
// Function to find the longest substring of 0's
static int longest_substring(String s, int k)
{
    // To store size of the string
    int n = s.length();
     
    if(k > 1)
    {
        s += s;
        n *= 2;
    }
     
    // To store the required answer
    int ans = 0;
     
    // Find the longest substring of 0's
    int i = 0;
    while (i < n)
    {
        int x = 0;
         
        // Run a loop upto s[i] is zero
        while (i < n && s.charAt(i) == '0')
        {
            x++; i++;
        }
        ans = Math.max(ans, x);
        i++;
    }
     
    // Check the conditions
    if(k == 1 || ans != n)
        return ans;
         
    else
        return (ans / 2) * k;
}
 
// Driver code
public static void main(String[] args)
{
    String s = "010001000";
     
    int k = 4;
     
    // Function call
    System.out.println(longest_substring(s, k));
}
}
 
// This code is contributed by Rajput-Ji

# Python3 program to find the find the Longest continuous
# sequence of '0' after repeating Given K time
 
# Function to find the longest subof 0's
def longest_substring(s, k):
    # To store size of the string
    n = len(s)
 
    if(k>1):
        s += s
        n *= 2
 
    # To store the required answer
    ans = 0
 
    # Find the longest subof 0's
    i = 0
    while (i < n):
        x = 0
 
        # Run a loop upto s[i] is zero
        while (i < n and s[i] == '0'):
            x,i=x+1, i+1
        ans = max(ans, x)
        i+=1
 
    # Check the conditions
    if(k==1 or ans!=n):
        return ans
 
    else:
        return (ans//2)*k
 
 
# Driver code
 
s = "010001000"
 
k = 4
 
# Function call
print(longest_substring(s, k))
 
# This code is contributed by mohit kumar 29

// C# program to find the Longest continuous
// sequence of '0' after repeating Given string K time
using System;
     
class GFG
{
 
// Function to find the longest substring of 0's
static int longest_substring(String s, int k)
{
    // To store size of the string
    int n = s.Length;
     
    if(k > 1)
    {
        s += s;
        n *= 2;
    }
     
    // To store the required answer
    int ans = 0;
     
    // Find the longest substring of 0's
    int i = 0;
    while (i < n)
    {
        int x = 0;
         
        // Run a loop upto s[i] is zero
        while (i < n && s[i] == '0')
        {
            x++; i++;
        }
        ans = Math.Max(ans, x);
        i++;
    }
     
    // Check the conditions
    if(k == 1 || ans != n)
        return ans;
         
    else
        return (ans / 2) * k;
}
 
// Driver code
public static void Main(String[] args)
{
    String s = "010001000";
     
    int k = 4;
     
    // Function call
    Console.WriteLine(longest_substring(s, k));
}
}
 
// This code is contributed by PrinciRaj1992

<script>
 
// Javascript program to find the find the Longest continuous
// sequence of '0' after repeating Given string K time
 
// Function to find the longest substring of 0's
function longest_substring(s, k)
{
    // To store size of the string
    var n = s.length;
     
    if(k>1)
    {
        s += s;
        n *= 2;
    }   
     
    // To store the required answer
    var ans = 0;
     
    // Find the longest substring of 0's
    var i = 0;
    while (i < n)
    {
        var x = 0;
         
        // Run a loop upto s[i] is zero
        while (s[i] == '0' && i < n)
            x++, i++;
        ans = Math.max(ans, x);
        i++;
    }
     
    // Check the conditions
    if(k==1 || ans!=n)
        return ans;
         
    else
        return (ans/2)*k;
}
 
// Driver code
var s = "010001000";
 
var k = 4;
 
// Function call
document.write( longest_substring(s, k));
 
</script>

Producción: 
 

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