leetcode

0 // The API isBadVersion is defined for you.

1 // bool isBadVersion(int version);

2

3 class Solution {

4 public:

5 int firstBadVersion(int n) {

6 int low = 1, high = n, last = -1;

7 while (low <= high) {

8 int mid = low + (high - low) / 2;

9 if (isBadVersion(mid))

10 high = (last = mid) - 1;

11 else

12 low = mid + 1;

13 }

14 return last;

15 }

16 };