Time: 72 ms (40.88%) | Memory: 87.7 MB (52.89%) - LeetSync

Author: sayandip20

2448-count-number-of-bad-pairs/count-number-of-bad-pairs.cpp

@@ -0,0 +1,15 @@
+class Solution {
+public:
+    long long countBadPairs(vector<int>& nums) {
+        unordered_map<int, int> freq;
+        long long goodPairs = 0, n = nums.size();
+        
+        for (int i = 0; i < n; i++) {
+            int key = nums[i] - i;
+            goodPairs += freq[key];
+            freq[key]++;
+        }
+        
+        return (n * (n - 1)) / 2 - goodPairs;
+    }
+};