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’ll tell you whether the number is higher or lower.

You call a pre-defined API `guess(int num)`

which returns 3 possible results (`-1`

, `1`

, or `0`

):

-1 : My number is lower 1 : My number is higher 0 : Congrats! You got it!

**Example:**

n = 10, I pick 6. Return 6.

/* 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; int compare = guess(mid); if (compare == 0) { return mid; } if (compare== 1) { low = mid + 1; } if (compare == -1) { high = mid - 1; } } return n; } }

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