原题链接：Leetcode 983. 最低票价

class Solution {
public:int mincostTickets(vector<int>& days, vector<int>& costs) {int n = days.size();int last = days[n - 1];int dp[last + 1];map<int, int> mp;for (auto x : days)mp[x] = 1;dp[0] = 0;int v1[3] = {1, 7, 30};for (int i = 1; i <= last; i++) {if (mp[i]) {dp[i] = INT_MAX;for (int k = 0; k < 3; k++) {dp[i] = min(dp[i], dp[max(i - v1[k], 0)] + costs[k]);}} else {dp[i] = dp[i - 1];}}return dp[last];}
};