167. Two Sum II - Input array is sorted

QUESTION:

Given an array of integers that is already sorted in ascending order, find two numbers such that they add up to a specific target number.

The function twoSum should return indices of the two numbers such that they add up to the target, where index1 must be less than index2. Please note that your returned answers (both index1 and index2) are not zero-based.

You may assume that each input would have exactly one solution and you may not use the same element twice.

Input: numbers={2, 7, 11, 15}, target=9 Output: index1=1, index2=2

EXPLANATION:

只要注意到这是一个有序的数组的话,那么注意有序数组的判断条件就可以节省很多时间,避免了TLE的问题。

SOLUTION:

public class Solution {
    public int[] twoSum(int[] nums, int target) {
        int[] result = new int[2];
        o: for (int i = 0; i < nums.length; i++) {
            if(nums[i]>target) break o;
            in: for (int j = i + 1; j < nums.length; j++) {
                if(nums[j]>target-nums[i]) break in;
                if (nums[i] + nums[j] == target) {
                    result[0] = i+1;
                    result[1] = j+1;
                    break o;
                }
            }
        }
        return result;
    }
}