paragon0107 s3sum

Author: paragon0107

3sum/paragon0107.java

@@ -0,0 +1,28 @@
+import java.util.Arrays;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+
+class Solution {
+    public List<List<Integer>> threeSum(int[] nums) {
+        Set<List<Integer>> set = new HashSet<>();
+        Arrays.sort(nums);
+        for (int i = 0; i < nums.length-2; i++) {
+            int start = i + 1;
+            int end = nums.length - 1;
+            while (start < end) {
+                int sum = nums[i] + nums[start] + nums[end];
+                if (sum < 0 ) {
+                    start++;
+                } else if (sum > 0) {
+                    end--;
+                }else {
+                    set.add(Arrays.asList(nums[i], nums[start], nums[end]));
+                    start++;
+                    end--;
+                }
+            }
+        }
+        return set.stream().toList();
+    }
+}