871. Minimum Number of Refueling Stops

难得，自己想出来的hard。

class Solution {
public:
    int minRefuelStops(int target, int startFuel, vector<vector<int>>& stations) {
        int remain = startFuel;
        priority_queue<int> pq;//留下的之前没有加的，不是遇到一个讨论现在要不要加，而是之后需要了再加
        int cnt = 0;
        int lastPos = 0;
        stations.push_back(vector<int>{target, 0});
        for (auto& station : stations) {
            int dist = station[0] - lastPos;
            lastPos = station[0];
            /*if (remain >= dist) {
                remain -= dist;
                pq.push(station[1]);
            } else {*/
                while (remain < dist) {
                    if (pq.empty())
                        return -1;
                    remain += pq.top();
                    pq.pop();
                    ++cnt;
                }
                remain -= dist;
                pq.push(station[1]);
            //}
        }
        return cnt;
    }
};

如果有一个站点到达不了，就加前面的最多的一个。