add 2sum.js

Johanes Boas Badia · abranhe · commit 82151f61835a · 2020-10-04T01:03:24.000-04:00
diff --git a/math/2sum.js b/math/2sum.js
@@ -0,0 +1,30 @@
+// File name: 2sum.js
+// Author: boasmarbun (https://github.com/boasmarbun)
+// Date created: 02/10/2020
+
+function twoSum (nums, target) {
+    var diff = 0;
+    for (var firstIndex = 0; firstIndex <= nums.length; firstIndex++) {
+        diff = target - nums[firstIndex];
+        var secondIndex = nums.indexOf(diff, firstIndex+1);
+        if(secondIndex != -1) {
+            return [firstIndex, secondIndex];
+        }
+    }
+    return [0];
+};
+
+// uncomment below for testing
+// var testArray1 = [1,2,3,9]
+// var target1 = 5
+// var testArray2 = [0,3,4,0]
+// var target2 = 0
+// var testArray3 = [-2, -3, -7, -13, -6]
+// var target3 = -8
+// var testArray4 = []
+// var target4 = 2
+
+// console.log(twoSum(testArray1, target1))
+// console.log(twoSum(testArray2, target2))
+// console.log(twoSum(testArray3, target3))
+// console.log(twoSum(testArray4, target4))
