1870. 准时到达的列车最小时速

题目链接：1870. 准时到达的列车最小时速

代码如下：

class Solution 
{
public:
	int minSpeedOnTime(vector<int>& dist, double hour)
	{
		long long h100 = round(hour * 100);
		long long delta = h100 - (dist.size() - 1) * 100;
		if (delta <= 0)//无法到达终点
		{
			return -1;
		}

		int max_dist = ranges::max(dist);
		if (h100 <= dist.size() * 100)
		{
			return max(max_dist, (int)((dist.back() * 100 - 1) / delta + 1));
		}
		auto check = [&](int v)->bool
			{
				long long t = 0;
				for (int i = 0; i < dist.size() - 1; i++)
				{
					t += (dist[i] - 1) / v + 1;
				}
				return (t * v + dist.back()) * 100 <= h100 * v;
			};
		
		int h = h100 / (dist.size() * 100);
		int left = 0, right = (max_dist - 1) / h + 1;
		while (left+1<right)
		{
			int mid = (left + right) / 2;
			(check(mid) ? right : left) = mid;
		}
		return right;
	}
};