9/5 每日一題(調用提供API 使用二分法)

 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 will tell you whether the number I picked is higher or lower than your guess.

You call a pre-defined API int guess(int num), which returns three possible results:

• -1: Your guess is higher than the number I picked (i.e. num > pick).
• 1: Your guess is lower than the number I picked (i.e. num < pick).
• 0: your guess is equal to the number I picked (i.e. num == pick).

Return the number that I picked.

 

Example 1:

Input: n = 10, pick = 6
Output: 6

Example 2:

Input: n = 1, pick = 1
Output: 1

Example 3:

Input: n = 2, pick = 1
Output: 1

 

Constraints:

• 1 <= n <= 231 - 1
• 1 <= pick <= n

# The guess API is already defined for you.

# @param num, your guess

# @return -1 if num is higher than the picked number

#          1 if num is lower than the picked number

#          otherwise return 0

# def guess(num: int) -> int:

class Solution:

    def guessNumber(self, n: int) -> int:

        left=1

        right=n

       

        while left <= right:

            mid = left +(right-left)//2

            if guess(mid)==0:

                return mid

            elif guess(mid) == 1:

                #還要更大

                left=mid+1

            else:

                #還要更小

                 right=mid-1

---------------------------------

# The guess API is already defined for you.
# @param num, your guess
# @return -1 if num is higher than the picked number
#          1 if num is lower than the picked number
#          otherwise return 0
# def guess(num: int) -> int:

class Solution:
    def guessNumber(self, n: int) -> int:      
        L, R = 1, n
        while L <= R:
            print(L, R)
            M = (L + R) // 2
            if guess(M) == 1:
                L = M + 1
            elif guess(M) == -1:
                R = M - 1
            else:
                return M
        return 0