two-sum

Author: taekwon-dev

two-sum/taekwon-dev.java

@@ -0,0 +1,18 @@
+/**
+ * 시간/공간 복잡도: O(n)
+ */
+class Solution {
+    public int[] twoSum(int[] nums, int target) {
+        Map<Integer, Integer> map = new HashMap<>();
+
+        for (int idx = 0; idx < nums.length; idx++) {
+            int complement = target - nums[idx];
+            if (map.containsKey(complement)) {
+                return new int[]{map.get(complement), idx};
+            }
+            map.put(nums[idx], idx);
+        }
+
+        return new int[]{-1, -1};
+    }
+}