力扣https://leetcode-cn.com/problems/car-pooling/

class Solution {
public:
    bool carPooling(vector<vector<int>>& trips, int capacity) {
        int delta[1024] = { 0 }; // delta[j]保存第j站变化的人数
        for (int i = 0; i < trips.size(); i++) {
            delta[trips[i][1]] += trips[i][0]; // trips[i][1]站上车的人数
            delta[trips[i][2]] -= trips[i][0]; // trips[i][2]站下车的人数
        }
        if (delta[0] > capacity) {
            return false;
        }
        int num = 0;
        for (int i = 0; i <= 1000; i++) {
            num += delta[i];
            if (num > capacity) {
                return false;
            }
        }
        return true;
    }
};