3sum solution

Author: dylan-jung

3sum/dylan-jung.cpp

@@ -0,0 +1,29 @@
+class Solution {
+public:
+    vector<vector<int>> threeSum(vector<int>& nums) {
+        sort(nums.begin(), nums.end());
+        vector<vector<int>> result;
+        for(int a = 0; a < nums.size()-2; a++) {
+            if (a > 0 && nums[a] == nums[a - 1]) continue;
+            int b = a + 1;
+            int c = nums.size() - 1;
+            while(b < c) {
+                if(nums[a] + nums[b] + nums[c] < 0) {
+                    b++;
+                }
+                else if (nums[a] + nums[b] + nums[c] > 0) {
+                    c--;
+                }
+                else {
+                    result.push_back({nums[a], nums[b], nums[c]});
+                    b++;
+                    c--;
+                    while (b < c && nums[b] == nums[b - 1]) b++;
+                    while (b < c && nums[c] == nums[c + 1]) c--;
+                }
+            }
+        }
+
+        return result;
+    }
+};