1069. 微博转发抽奖(20)

// 2017/10/14 NCU
// PAT-B 1070
// scienceZ
#include <cstdio>
#include <set>
#include <string>
#include <iostream>
#include <algorithm>
using namespace std;

int m, n, s;
char arr[1005][30];
set<string> bi;

int main()
{
cin >> m >> n >> s;
for (int i = 1; i <= m; i++) cin >> arr[i];

for(int i = s; i<=m; ){
if(bi.count(arr[i]) == 1) {
i++;
continue;
}else{
cout << arr[i] <<  endl;
bi.insert(arr[i]);
i+=n;
}
}
if (bi.size() == 0) cout << "Keep going..." << endl;
return 0;
}