Ice cream samples Gym - 101670G 滑动扫描

题目：题目链接

思路：比赛中读错了题，题目要求选一个连续区间，却读成了随便选取几个柜台，英语要好好学啊，读懂题就很简单了，扫一遍就出结果了

AC代码：

 #include <iostream>
 #include <cstdio>
 #include <cstdlib>
 #include <cmath>
 #include <algorithm>
 #include <cstring>
 #include <vector>
 #include <string>
 #include <queue>
 #include <map>
 #include <set>

 #define FRER() freopen("in.txt", "r", stdin);
 #define INF 0x3f3f3f3f

 using namespace std;

 const int maxn =  + ;

 vector<int> stand[maxn << ];

 int brand[maxn], N, K;

 void init() {
     for(int i = ; i < (N << ); ++i)
         stand[i].clear();
     memset(brand, , sizeof(brand));
 }

 int solve() {
     int st = , ed = , ans = INF, k = , now = ;
     while(ed < (N << )) {
         for(int i = ; i < stand[ed].size(); ++i) {
             ++now;
             if(brand[stand[ed][i]] == )
                 ++k;
             ++brand[stand[ed][i]];
         }
         ++ed;
         while(k == K && st < ed) {
             ans = min(ans, now);
             for(int i = ; i < stand[st].size(); ++i) {
                 --now;
                 --brand[stand[st][i]];
                 if(brand[stand[st][i]] == )
                     --k;
             }
             ++st;
         }
     }
     return ans == INF ? - : ans;
 }

 int main()
 {
     //FRER()
     while(~scanf("%d %d", &N, &K)) {
         init();
         int n, num;
         for(int i = ; i < N; ++i) {
             scanf("%d", &n);
             for(int j = ; j < n; ++j) {
                 scanf("%d", &num);
                 stand[i].push_back(num);
                 stand[i + N].push_back(num);
             }
         }
         printf("%d\n", solve());
     }
     return ;
 }