Create Two sum

Two sum

@@ -0,0 +1,31 @@
+<!----
+Given an array of integers nums and an integer target, return indices of the two numbers such that they add up to target.
+
+You may assume that each input would have exactly one solution, and you may not use the same element twice.
+
+You can return the answer in any order.
+
+
+
+Example 1:
+
+Input: nums = [2,7,11,15], target = 9
+Output: [0,1]
+Output: Because nums[0] + nums[1] == 9, we return [0, 1].
+-->
+
+class Solution {
+    public int[] twoSum(int[] nums, int target) {
+        Map<Integer, Integer> num_map  = new HashMap<Integer, Integer>();
+
+        for(int i=0; i<nums.length; i++){
+            int complement = target - nums[i];
+
+          if (num_map.containsKey(complement)){
+              return new int[] {(num_map.get(complement)), i};
+          }  
+        num_map.put(nums[i], i);
+    }
+        throw new  IllegalArgumentException("no match found ");
+   } 
+}