Recuento de subsecuencias ‘GFG’ en la string dada

Dada una string de longitud n de letras mayúsculas. La tarea es encontrar el recuento de la subsecuencia ‘GFG’ en la string dada.
Ejemplos: 
 

Input : str[] = "GFGFG"
Output : 4
GFGFG, GFGFG, GFGFG, GFGFG

Input : str[] = "ABCFGFPG"
Output : 1

// CPP Program to find the "GFG" subsequence in
// the given string
#include <bits/stdc++.h>
using namespace std;
#define MAX 100
  
// Print the count of "GFG" subsequence in the string
void countSubsequence(char s[], int n)
{
    int cntG = 0, cntF = 0, result = 0, C=0;
  
    // Traversing the given string
    for (int i = 0; i < n; i++) {
        switch (s[i]) {
  
        // If the character is 'G', increment
        // the count of 'G', increase the result
        // and update the array.
        case 'G':
            cntG++;
            result+=C;
            break;
  
        // If the character is 'F', increment
        // the count of 'F' and update the array.
        case 'F':
            cntF++;
            C+=cntG;
            break;
  
        // Ignore other character.
        default:
            continue;
        }
    }
  
    cout << result << endl;
}
  
// Driven Program
int main()
{
    char s[] = "GFGFG";
    int n = strlen(s);
    countSubsequence(s, n);
    return 0;
}

// Java Program to find the "GFG" subsequence
// in the given string
  
public class GFG {
  
    static int max = 100;
          
    // Print the count of "GFG" subsequence
    // in the string
    static void countSubsequence(String s, int n)
    {
        int cntG = 0, cntF = 0, result = 0, C=0;
      
        // Traversing the given string
        for (int i = 0; i < n; i++) {
            switch (s.charAt(i)) {
      
            // If the character is 'G', 
            // increment the count of 'G',
            // increase the result and 
            // update the array.
            case 'G':
                cntG++;
                result+=C;
                break;
      
            // If the character is 'F', 
            // increment the count of 'F'
            // and update the array.
            case 'F':
                cntF++;
                C+=cntG;
                break;
      
            // Ignore other character.
            default:
                continue;
            }
        }
      
        System.out.println(result);
    }
      
    // Driver code    
    public static void main(String args[]) {
        String s= "GFGFG";
        int n = s.length();
        countSubsequence(s, n);
    }
}
  
// This code is contributed by Sam007

# Python 3 Program to find the "GFG" 
# subsequence in the given string
MAX = 100
  
# Print the count of "GFG" subsequence 
# in the string
def countSubsequence(s, n):
    cntG = 0
    cntF = 0
    result = 0
    C=0
  
  
    # Traversing the given string
    for i in range(n):
        if (s[i] == 'G'):
              
            # If the character is 'G', increment
            # the count of 'G', increase the result
            # and update the array.
            cntG += 1
            result += C
            continue
  
        # If the character is 'F', increment
        # the count of 'F' and update the array.
        if (s[i] == 'F'):
            cntF += 1
            C += cntG
            continue
  
        # Ignore other character.
        else:
            continue
      
    print(result)
  
# Driver Code
if __name__ == '__main__':
    s = "GFGFG"
    n = len(s)
    countSubsequence(s, n)
      
# This code is contributed by
# Sanjit_Prasad

// C# Program to find the "GFG" subsequence
// in the given string
using System;
  
class GFG {
          
    // Print the count of "GFG" subsequence
    // in the string
    static void countSubsequence(string s,
                                     int n)
    {
        int cntG = 0, cntF = 0, result = 0, C=0;
      
        // Traversing the given string
        for (int i = 0; i < n; i++) {
            switch (s[i]) {
      
            // If the character is 'G', 
            // increment the count of 'G',
            // increase the result and 
            // update the array.
            case 'G':
                cntG++;
                result += C;
                break;
      
            // If the character is 'F', 
            // increment the count of 'F'
            // and update the array.
            case 'F':
                cntF++;
                C+=cntG;
                break;
      
            // Ignore other character.
            default:
                continue;
            }
        }
      
        Console.WriteLine(result);
    }
      
    // Driver code
    public static void Main()
    {
        string s= "GFGFG";
        int n = s.Length;
        countSubsequence(s, n);
    }
}
  
// This code is contributed by Sam007.

<script>
  
  
// Javascript Program to find the "GFG" subsequence in
// the given string
var MAX = 100;
  
// Print the count of "GFG" subsequence in the string
function countSubsequence( s, n)
{
    var cntG = 0, cntF = 0, result = 0, C=0;
  
    // Traversing the given string
    for (var i = 0; i < n; i++) {
        switch (s[i]) {
  
        // If the character is 'G', increment
        // the count of 'G', increase the result
        // and update the array.
        case 'G':
            cntG++;
            result+=C;
            break;
  
        // If the character is 'F', increment
        // the count of 'F' and update the array.
        case 'F':
            cntF++;
            C+=cntG;
            break;
  
        // Ignore other character.
        default:
            continue;
        }
    }
  
    document.write( result );
}
  
// Driven Program
var s = "GFGFG";
var n = (s.length);
countSubsequence(s, n);
  
// This code is contributed by itsok.
</script>