力扣2594.修车的最少时间

力扣2594.修车的最少时间

• 二分答案

•   class Solution {
    public:
        long long repairCars(vector<int>& ranks, int cars) {
            ranges::sort(ranks);
            auto check = [&](long long x) -> bool
            {
                long long res = 0;
                for(auto v : ranks)
                {
                    long long k = sqrt(x/v);
                    res += k;
                    if(res >= cars) return true;
                }
                return false;
            };
            long long l = 1,r = (long long)ranks[0]*cars*cars;
            while(l < r)
            {
                long long mid = (l+r)/2;
                if(check(mid)) r = mid;
                else l = mid + 1;
            }
            return l;
        }
    };