C语言双指针法

167. 两数之和 II - 输入有序数组 - 力扣（LeetCode）

 

/**
 * Note: The returned array must be malloced, assume caller calls free().
 */
int* twoSum(int* numbers, int numbersSize, int target, int* returnSize){

    // 双指针法
    int left = 0;
    int right = numbersSize - 1;
    * returnSize = 2;
    int* result = (int*)malloc(numbersSize*sizeof(int));

    while (left < right){
        if (numbers[left] + numbers[right] == target){
            result[0] = left + 1;
            result[1] = right + 1;
            return result;
        }
        else if ( numbers[left] + numbers[right] >= target){
            right--;
        }
        else if (numbers[left] + numbers[right] <= target){
            left++;
        }
    }

    result[0] = -1;
    result[1] = -1;
    return result;

}