C# 代码

public class Solution {
    public long RepairCars(int[] ranks, int cars) {
        int n = ranks.Length;
        long left = 1, right = long.MaxValue;
        while (left < right){
            long mid = left + (right - left >> 1);
            if (Check(mid)) right = mid;
            else left = mid + 1;
        }

        return left;

        bool Check(long x){
            long ans = 0;
            for (int i = 0; i < n; i++){
                ans += (long)Math.Sqrt(x / ranks[i]);
                if (ans >= cars) return true;
            }

            return ans >= cars;
        }
    }
}