LeetCode-Java/3Sum at main · dhinith2007/LeetCode-Java · GitHub

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LEETCODE PROBLEM SOLVING
PROBLEM->3SUM
import java.util.*;

class Solution {

    public List<List<Integer>> threeSum(int[] nums) {

        List<List<Integer>> result = new ArrayList<>();

        Arrays.sort(nums);

        for (int i = 0; i < nums.length - 2; i++) {
            if (i > 0 && nums[i] == nums[i - 1])
                continue;

            int left = i + 1;
            int right = nums.length - 1;

            while (left < right) {

                int sum = nums[i] + nums[left] + nums[right];

                if (sum == 0) {

                    result.add(Arrays.asList(nums[i], nums[left], nums[right]));

                    left++;
                    right--;
                    while (left < right &&
                           nums[left] == nums[left - 1])
                        left++;
                    while (left < right &&
                           nums[right] == nums[right + 1])
                        right--;

                }

                else if (sum < 0) {

                    left++;

                }

                else {

                    right--;
                }
            }
        }

        return result;
    }
}