Three Sum Array Problem in C++

Three Sum Array Problem in C++

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+#include <iostream>
+#include <vector>
+#include <algorithm>
+
+using namespace std;
+
+vector<vector<int>> threeSum(vector<int>& nums) {
+    vector<vector<int>> result;
+    int n = nums.size();
+
+    // Sort the array
+    sort(nums.begin(), nums.end());
+
+    // Iterate over the array
+    for (int i = 0; i < n - 2; ++i) {
+        // Avoid duplicates for the first element
+        if (i > 0 && nums[i] == nums[i - 1]) continue;
+
+        int left = i + 1;
+        int right = n - 1;
+
+        while (left < right) {
+            int sum = nums[i] + nums[left] + nums[right];
+
+            if (sum == 0) {
+                result.push_back({nums[i], nums[left], nums[right]});
+
+                // Avoid duplicates for the second element
+                while (left < right && nums[left] == nums[left + 1]) left++;
+                // Avoid duplicates for the third element
+                while (left < right && nums[right] == nums[right - 1]) right--;
+
+                // Move both pointers inward
+                left++;
+                right--;
+            }
+            else if (sum < 0) {
+                left++;
+            }
+            else {
+                right--;
+            }
+        }
+    }
+
+    return result;
+}
+
+int main() {
+    vector<int> nums = {-1, 0, 1, 2, -1, -4};
+
+    vector<vector<int>> result = threeSum(nums);
+
+    // Print the result
+    cout << "Triplets with sum 0 are:" << endl;
+    for (auto& triplet : result) {
+        cout << "[";
+        for (int i = 0; i < triplet.size(); ++i) {
+            cout << triplet[i];
+            if (i < triplet.size() - 1) cout << ", ";
+        }
+        cout << "]" << endl;
+    }
+
+    return 0;
+}