/**
* Forward declaration of guess API.
* @param num your guess
* @return -1 if num is lower than the guess number
* 1 if num is higher than the guess number
* otherwise return 0
* int guess(int num);
*/intguess(int num);classSolution{public:intguessNumber(int n){unsignedint left =1, right = n;while(left <= right){unsignedint mid =(left + right)/2;unsignedint res =guess(mid);if(res ==0)return mid;elseif(res ==1)
left = mid +1;else
right = mid -1;}return0;}};