PAT_A1124#Raffle for Weibo Followers

Posted 2022-03-15 blue-lin

Source:

PAT A1124 Raffle for Weibo Followers (20 分)

Description:

John got a full mark on PAT. He was so happy that he decided to hold a raffle（抽奖） for his followers on Weibo -- that is, he would select winners from every N followers who forwarded his post, and give away gifts. Now you are supposed to help him generate the list of winners.

Input Specification:

Each input file contains one test case. For each case, the first line gives three positive integers M (≤1000), N and S, being the total number of forwards, the skip number of winners, and the index of the first winner (the indices start from 1). Then M lines follow, each gives the nickname (a nonempty string of no more than 20 characters, with no white space or return) of a follower who has forwarded John‘s post.

Note: it is possible that someone would forward more than once, but no one can win more than once. Hence if the current candidate of a winner has won before, we must skip him/her and consider the next one.

Output Specification:

For each case, print the list of winners in the same order as in the input, each nickname occupies a line. If there is no winner yet, print Keep going... instead.

Sample Input 1:

9 3 2
Imgonnawin!
PickMe
PickMeMeMeee
LookHere
Imgonnawin!
TryAgainAgain
TryAgainAgain
Imgonnawin!
TryAgainAgain

Sample Output 1:

PickMe
Imgonnawin!
TryAgainAgain

Sample Input 2:

2 3 5
Imgonnawin!
PickMe

Sample Output 2:

Keep going...

Keys:

• 模拟题

Code:

 1 /*
 2 Data: 2019-07-04 15:00:05
 3 Problem: PAT_A1124#Raffle for Weibo Followers
 4 AC: 25:52
 5 
 6 题目大意：
 7 从转发微博的名单中抽奖，每隔N人送一份奖品
 8 输入：
 9 第一行给出，转发数M<=1000，获奖者间隔的人数N，第一个获奖者序号S>=1
10 接下来M行，转发人的昵称
11 注：若选定的获奖者如果已经获奖，则考虑下一个人
12 输出：
13 打印获奖者名单
14 
15 基本思路：
16 从S开始遍历名单，计数器统计跳过人数，跳过n人时进行查询
17 若未获奖，计数器清零，打印姓名
18 若已获奖，计数器不变，查询下一位
19 */
20 #include<cstdio>
21 #include<string>
22 #include<map>
23 #include<iostream>
24 using namespace std;
25 const int M=1e3+10;
26 string info[M];
27 map<string,int> mp;
28 
29 int main()
30 
31 #ifdef    ONLINE_JUDGE
32 #else
33     freopen("Test.txt", "r", stdin);
34 #endif
35 
36     int m,n,s,skip=0;
37     scanf("%d%d%d", &m,&n,&s);
38     for(int i=1; i<=m; i++)
39         cin >> info[i];
40     for(int i=s; i<=m; i++)
41     
42         if(i==s || skip==n)
43         
44             if(mp[info[i]]==0)
45                 cout << info[i] << endl;
46                 mp[info[i]]=1;
47                 skip=0;
48             
49             else
50                 continue;
51         
52         skip++;
53     
54     if(s > m)
55         printf("Keep going...");
56 
57     return 0;
58