LeetCode 374. Guess Number Higher or Lower

We are playing the Guess Game. The game is as follows:

I pick a number from 1 to n. You have to guess which number I picked.

Every time you guess wrong, I'll tell you whether the number is higher or lower.

You call a pre-defined API guess(int num) which returns 3 possible results (-1, 1, or 0):

-1 : My number is lower

 1 : My number is higher

 0 : Congrats! You got it!

Example:

n = 10, I pick 6.

Return 6.

一个二分查找

// Forward declaration of guess API.

// @param num, your guess

// @return -1 if my number is lower, 1 if my number is higher, otherwise return 0

int guess(int num);

class Solution {

public:

    int guessNumber(int n) {

        long long start=,end=n;

        long long mid=(start+end+)/;

        if(==guess(start))return start;

        while(guess(mid))

        {

            if(-==guess(mid))

            {

                end=mid-;

                mid=(start+end+)/;

            }

            if(==guess(mid))

            {

                start=mid+;

                if(==guess(start))return start;

                mid=(start+end+)/;

            }

        }

        return mid;

    }

};

巴特西

LeetCode 374. Guess Number Higher or Lower

最新文章

热门文章