8-31每日一题：Leetcode1109. 航班预订统计

航班预订统计

思路：差分

前缀和的逆运算，最后还原返回$vector$的前n个

class Solution {
public:
    vector<int> corpFlightBookings(vector<vector<int>>& bookings, int n) {
        vector<int> book(n + 1);
        int m = bookings.size();
        for (int i = 0; i < m; i ++ ) {
            book[bookings[i][0] - 1] += bookings[i][2];
            book[bookings[i][1]] -= bookings[i][2];
        }

        for (int i = 1; i < n; i ++ ) {
            book[i] += book[i - 1];
        }
        return vector<int>(book.begin(), book.begin() + n);
    }
};