# \#374 Guess Number Higher or Lower ## *簡單描述題目* ## Log - build 20210710 by syhuang ## 初見 - 二分法查找 - 注意邊界 ```javascript= var guessNumber = function(n) { if(guess(n)==0) return n; if(guess(1)==0) return 1; let left = 1; let right = n; let result; while(right-left>1){ let mid = left + Math.ceil((right-left)/2); let check = guess(mid); if(check==-1) right = mid; else if(check==1) left = mid else { result = mid; break; } } return result; }; ``` ## 備註 ## 參考 ###### tags: `leetcode`, `leetcode-easy`