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`