https://leetcode.cn/problems/subarray-sum-equals-k

Author: masx200

README.md

@@ -2614,4 +2614,6 @@ https://leetcode.cn/problems/count-vowel-strings-in-ranges
 
 https://leetcode.cn/problems/maximum-number-of-weeks-for-which-you-can-work
 
+https://leetcode.cn/problems/subarray-sum-equals-k
+
 </details>

subarray-sum-equals-k/index.ts

@@ -0,0 +1,18 @@
+function subarraySum(nums: number[], k: number) {
+    const mp = new Map<number, number>();
+    mp.set(0, 1);
+    let count = 0, pre = 0;
+    for (const x of nums) {
+        pre += x;
+        if (mp.has(pre - k)) {
+            count += mp.get(pre - k) ?? 0;
+        }
+        if (mp.has(pre)) {
+            mp.set(pre, (mp.get(pre) ?? 0) + 1);
+        } else {
+            mp.set(pre, 1);
+        }
+    }
+    return count;
+}
+export default subarraySum;