leetcode 374—注意溢出，二分左边界，右边界

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本文详细解析了LeetCode上猜数字游戏的算法实现。通过二分查找的方式逐步缩小猜测范围，最终找到目标数字。该算法适用于任何需要在有序范围内进行高效搜索的场景。

题目链接：

https://leetcode.com/problems/guess-number-higher-or-lower/

正解：

// 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) {
        int l=1;
        int r=n;
        int guessOne=l+(r-l)/2;
        int guessAns=guess(guessOne);
        while (guessAns!=0) {
            if (guessAns==1) {
                l=guessOne+1;
                guessOne=l+(r-l)/2;
                guessAns=guess(guessOne);
            }else{
                r=guessOne-1;
                guessOne=l+(r-l)/2;
                guessAns=guess(guessOne);
            }
        }
        return guessOne;
    }
};