Added pairSum

Sheet400-C++/Arrays/pairSum.cpp

@@ -0,0 +1,33 @@
+#include <iostream>
+#include <vector>
+using namespace std;
+
+vector<vector<int>> pairSum(vector<int> &arr, int s){
+    vector<vector<int>> ans;
+
+    for(int i = 0; i < arr.size(); i++){
+        for(int j = i+1; j < arr.size(); j++){
+            if(arr[i] + arr[j] == s){
+                vector<int> temp;
+                temp.push_back(min(arr[i], arr[j]));
+                temp.push_back(max(arr[i], arr[j]));
+                ans.push_back(temp);
+            }
+        }
+    }
+
+    sort(ans.begin(), ans.end());
+    return ans
+}
+
+int main() {
+    int arr[100];
+    int size;
+    cin >> size;
+
+    for(int i = 0; i < size; i++){
+        cin >> arr[i];
+    }
+    cout << pairSum(arr, size) << endl;
+
+}