created file pair with sum

Author: Shubham9993

pair-sum.cpp

@@ -0,0 +1,31 @@
+
+// C++ implementation of simple method to find count of 
+// pairs with given sum. 
+#include <bits/stdc++.h> 
+using namespace std; 
+  
+// Returns number of pairs in arr[0..n-1] with sum equal 
+// to 'sum' 
+int getPairsCount(int arr[], int n, int sum) 
+{ 
+    int count = 0; // Initialize result 
+  
+    // Consider all possible pairs and check their sums 
+    for (int i=0; i<n; i++) 
+        for (int j=i+1; j<n; j++) 
+            if (arr[i]+arr[j] == sum) 
+                count++; 
+  
+    return count; 
+} 
+  
+// Driver function to test the above function 
+int main() 
+{ 
+    int arr[] = {1, 5, 7, -1, 5} ; 
+    int n = sizeof(arr)/sizeof(arr[0]); 
+    int sum = 6; 
+    cout << "Count of pairs is " 
+         << getPairsCount(arr, n, sum); 
+    return 0; 
+}