test markdown style

code

// Forward declaration of isBadVersion API.
bool isBadVersion(int version);

class Solution {
public:
    int firstBadVersion(int n) {
        int l = 1;
        int r = n;
        int m;
        while (l <= r) {
            m = l + (r - l) / 2;
            if (isBadVersion(m)) r = m - 1;
            else l = m + 1;
        }
        return l;
    }
};