#include<bits/stdc++.h>

#define LL long long

#define fi first

#define se second

#define mk make_pair

#define PLL pair<LL, LL>

#define PLI pair<LL, int>

#define PII pair<int, int>

#define SZ(x) ((int)x.size())

#define ull unsigned long long

using namespace std;

const int N = 1e5 + ;

const int inf = 0x3f3f3f3f;

const LL INF = 0x3f3f3f3f3f3f3f3f;

const int mod = ;

const double eps = 1e-;

const double PI = acos(-);

char s[];

int getIn() {

    int n; scanf("%d", &n);

    for(int i = ; i <= n; i++) scanf("%s", s);

    return n;

}

int main() {

    while() {

        printf("next 0\n"); fflush(stdout);

        getIn();

        printf("next 0 1\n"); fflush(stdout);

        if(getIn() == ) break;

    }

    while() {

        printf("next 0 1 2 3 4 5 6 7 8 9\n"); fflush(stdout);

        if(getIn() == ) break;

    }

    printf("done\n");

    fflush(stdout);

    return ;

}

/*

*/