Day68

swolecoder · swolecoder · commit 99bd944f6d88 · 2020-12-17T09:48:38.000-05:00
diff --git a/Day68/index.js b/Day68/index.js
@@ -0,0 +1,37 @@
+/**
+ * @param {number[]} A
+ * @param {number[]} B
+ * @param {number[]} C
+ * @param {number[]} D
+ * @return {number}
+ */
+var fourSumCount = function (A, B, C, D) {
+
+    let map = {};
+    let count = 0;
+
+    for (let i = 0; i < A.length; i++) {
+        for (let j = 0; j < B.length; j++) {
+            let sum = A[i] + B[j];
+
+            if (!(sum in map)) {
+                map[sum] = 1;
+            } else {
+                map[sum]++;
+            }
+        }
+    }
+
+    for (let i = 0; i < C.length; i++) {
+        for (let j = 0; j < D.length; j++) {
+            let sum = C[i] + D[j];
+
+            if (map[-sum] != null) {
+                count += map[-sum]
+            }
+        }
+    }
+
+
+    return count;
+};
diff --git a/README.md b/README.md
@@ -151,4 +151,6 @@ If you are loving solving problems in leetcode, please contact me to enjoy it to
 
 |Day 66| [1485. Clone Binary Tree With Random Pointer](https://leetcode.com/problems/clone-binary-tree-with-random-pointer/) | [javascript]()|[:memo:](https://leetcode.com/problems/clone-binary-tree-with-random-pointer/)|Medium|
 
-|Day 67| [98. Validate Binary Search Tree](https://leetcode.com/problems/validate-binary-search-tree/) | [javascript]()|[:memo:](https://leetcode.com/problems/validate-binary-search-tree/)|Medium|
+|Day 67| [98. Validate Binary Search Tree](https://leetcode.com/problems/validate-binary-search-tree/) | [javascript]()|[:memo:](https://leetcode.com/problems/validate-binary-search-tree/)|Medium|
+
+|Day 68| [454. 4Sum II](https://leetcode.com/problems/4sum-ii/) | [javascript]()|[:memo:](https://leetcode.com/problems/4sum-ii/)|Medium|
