015 Solution.cpp supplement

Author: KongJHong

solution/0015.3Sum/Solution.cpp

@@ -0,0 +1,40 @@
+class Solution {
+public:
+    vector<vector<int>> threeSum(vector<int>& nums) {
+        sort(nums.begin(),nums.end());
+
+        vector<vector<int>> ans;
+        
+        int sum;
+        int len = nums.size();
+        int left,right;
+        for(int i = 0; i< len;i++){
+            left = i + 1;
+            right = len - 1;
+            while(left < right){
+                sum = nums[i] + nums[left] + nums[right];
+                if(sum == 0){
+                    vector<int> vec;
+                    vec.push_back(nums[i]);
+                    vec.push_back(nums[left]);
+                    vec.push_back(nums[right]);
+                    ans.push_back(vec);
+                    
+                    while(left < right && nums[left] == nums[left + 1])left++;
+                    while(left < right && nums[right] == nums[right - 1])right--;
+                    
+                    left++;
+                    right--;
+                    
+                }
+                if(sum > 0)right--;
+                if(sum < 0)left++;
+            }
+            
+            while(i<len-1 && nums[i] == nums[i+1])i++;
+        }
+        
+        return ans;
+        
+    }
+};