136 Single Number

malipramod · malipramod · commit c38f5f0fe266 · 2019-09-03T17:26:49.000+05:30
diff --git a/easy/0136 single-number/readme.md b/easy/0136 single-number/readme.md
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+# Single Number
+
+Given a non-empty array of integers, every element appears twice except for one. Find that single one.
+
+## Note
+
+Your algorithm should have a linear runtime complexity. Could you implement it without using extra memory?
+
+## Example 1
+
+Input: [2,2,1]
+
+Output: 1
+
+## Example 2
+
+Input: [4,1,2,1,2]
+
+Output: 4
+
+## More Info
+
+<https://leetcode.com/problems/single-number/>
diff --git a/easy/0136 single-number/single-number.js b/easy/0136 single-number/single-number.js
@@ -0,0 +1,15 @@
+/**
+ * @param {number[]} nums
+ * @return {number}
+ */
+var singleNumber = function(nums) {
+    let myMap = {};
+    for (let i = 0; i < nums.length; i++) { 
+        myMap[nums[i]] = myMap[nums[i]] == undefined ? 1 : ++myMap[nums[i]];
+    }
+    for(key in myMap){
+        if(myMap[key] === 1) return Math.floor(key)
+    }
+};
+
+console.log(singleNumber([4,1,2,1,2]))
