problem no 48:sorting problem:find the triplet inside the array that sum up to the given particular value.

 QUESTION:

Triplet Sum in Array

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Given an array arr of size arr_size and an integer sum. Find if there's a triplet in the array which sums up to the given integer sum.

Example 1:

Input:
N = 6, X = 13
arr[] = [1 4 45 6 10 8]
Output:
1
Explanation:
The triplet {1, 4, 8} in 
the array sums up to 13.

Example 2:

Input:
N = 5, X = 10
arr[] = [1 2 4 3 6]
Output:
1
Explanation:
The triplet {1, 3, 6} in 
the array sums up to 10. 

ANSWER:

bool find3Numbers(int A[], int arr_size, int sum)
{
     int l, r; 
  
   
    sort(A, A + arr_size); 
  
    
    for (int i = 0; i < arr_size - 2; i++) { 
  
        
        l = i + 1; 
  
        r = arr_size - 1; 
        while (l < r) { 
            if (A[i] + A[l] + A[r] == sum) { 
                
                return true; 
            } 
            else if (A[i] + A[l] + A[r] < sum) 
                l++; 
            else // A[i] + A[l] + A[r] > sum 
                r--; 
        } 
    } 
  
    // If we reach here, then no triplet was found 
    return false; 
}