add Easy_349_Intersection_of_Two_Arrays

zongyanqi · zongyanqi · commit 09d99f1e1330 · 2017-03-19T22:16:49.000+08:00
diff --git a/Easy_349_Intersection_of_Two_Arrays.js b/Easy_349_Intersection_of_Two_Arrays.js
@@ -0,0 +1,35 @@
+/**
+ * Given two arrays, write a function to compute their intersection.
+
+ Example:
+ Given nums1 = [1, 2, 2, 1], nums2 = [2, 2], return [2].
+
+ Note:
+ Each element in the result must be unique.
+ The result can be in any order.
+ */
+
+/**
+ * @param {number[]} nums1
+ * @param {number[]} nums2
+ * @return {number[]}
+ */
+var intersection = function (nums1, nums2) {
+
+    var ret = [];
+    var map1 = nums1.reduce((map, n) => {
+        if (!map[n]) map[n] = 1;
+        return map;
+    }, {});
+
+    var map2 = nums2.reduce((map, n) => {
+        if (map1[n] && !map[n]) {
+            ret.push(n);
+            map[n] = 1;
+        }
+        return map;
+    }, {});
+
+    return ret;
+};
+console.log(intersection([1, 2, 2, 1], [2, 2]));
