Create 560-subarray-sum-equals-k.js

aadil42 · web-flow · commit bba761e7aa02 · 2022-11-07T15:06:56.000+05:30
Solved subarray sum equals k in JS.
diff --git a/javascript/560-subarray-sum-equals-k.js b/javascript/560-subarray-sum-equals-k.js
@@ -0,0 +1,23 @@
+// Problem link https://leetcode.com/problems/subarray-sum-equals-k
+// Time Complexity: O(n)
+
+
+var subarraySum = function(nums, k) {
+
+
+
+const prefixMap = {};
+let totalSubArray = 0;
+let ongoingSum = 0;
+
+prefixMap[0] = 1;
+for(let i = 0; i < nums.length; i++) {
+    ongoingSum += nums[i];
+    if(prefixMap[ongoingSum - k]){
+        totalSubArray += prefixMap[ongoingSum - k];
+    }
+    prefixMap[ongoingSum] = (prefixMap[ongoingSum] ? prefixMap[ongoingSum] + 1: 1);
+}
+
+return totalSubArray;
+};
