long long ans = -1;
    while (left <= right)
    {
        long long mid = (left + right) / 2;
        // std::cout << mid;
        if (check(mid))
        {
            left = mid + 1;
            ans = mid;
        }
        else
        {
            right = mid - 1;
        }
    }

挂了八号（95）

    long long ans = -1;
    while (left < right)
    {
        long long mid = (left + right) / 2;
        // std::cout << mid;
        if (check(mid))
        {
            left = mid + 1;
            ans = mid;
        }
        else
        {
            right = mid ;
        }
    }

挂了三号（95）

    long long ans = -1;
    while (left <= right)
    {
        long long mid = (left + right) / 2;
        // std::cout << mid;
        if (check(mid))
        {
            left = mid + 1;
            ans = mid;
        }
        else
        {
            right = mid - 1;
        }
    }

挂了14号(95)

    long long ans = -1;
    while (left <= right)
    {
        long long mid = (left + right) / 2;
        // std::cout << mid;
        if (check(mid))
        {
            left = mid + 1;
            ans = mid;
        }
        else
        {
            right = mid - 1;
        }
    }

满分