leetcode 374. Guess Number Higher or Lower 解题报告

原题链接

解题思路

解题代码

/* The guess API is defined in the parent class GuessGame.
@param num, your guess
@return -1 if my number is lower, 1 if my number is higher, otherwise return 0
int guess(int num); */

public class Solution extends GuessGame {
public int guessNumber(int n) {
int low = 1;
int high = n;
while(low <= high) {
int mid = low + (high - low)/2;
if (guess(mid) == 0) {
return mid;
} else if (guess(mid) == -1) {
high = mid - 1;
} else {
low = mid + 1;
}
}
return -1;
}
}