#include <bits/stdc++.h>   using namespace std;   #define rep(i,a,b) for(int i = (a); i < b; ++i)   #define rrep(i,a,b) for(int i = (b); i --> (a);)   #define trav(x, v) for(auto &x : v)   #define all(v) (v).begin(),(v).end()   #define sz(v) (int)(v).size()      bool que_big(int s, string x){    cout << s+1 <<     << x << endl;    string res;    cin >> res;    return res ==  yes ;   }      int main(){    int n = 200, b = 200;    cin >> n >> b;       vector<string> ub(n, string(b,  1 ));    string lb(b,  0 );    deque<int> ko;    rep(i,0,n) ko.push_back(i);    string nxt = string(b,  1 );    nxt[0] =  0 ;    while(true){     int s = ko.front();     if(ub[s] < lb){      ko.pop_front();      continue;     }     if(ub[s] == lb){      cout << 0 <<     << lb << endl;      return 0;     }     if(que_big(s, nxt)){      lb = nxt;      rrep(i,0,b){       if(lb[i]== 0 ){        lb[i] =  1 ;        nxt[i] =  1 ;        break;       } else {        lb[i] =  0 ;       }      }     } else {      ub[s] = nxt;      ko.pop_front();      ko.push_back(s);      rep(i,0,b) if(nxt[i] > lb[i]){       nxt[i] =  0 ;       break;      }     }    }   }   