add solution of two-sum

Author: jinhyungrhee

two-sum/jinhyungrhee.java

@@ -0,0 +1,17 @@
+class Solution {
+
+    // Method1. brute-force => O(N^2)
+    public int[] twoSum(int[] nums, int target) {
+        int size = nums.length;
+        int[] answer = new int[2];
+        for (int i = 0; i < size; i++) {
+            for (int j = i + 1; j < size; j++) {
+                if (nums[i] + nums[j] == target) {
+                    answer[0] = i;
+                    answer[1] = j;
+                }
+            }
+        }
+        return answer;
+    }
+}