#include<bits/stdc++.h>   using namespace std;   #define int long long      int n, k;      int mod(int i){return (i%n+n)%n;}      int q(int x){    x = mod(x) + 1;    cout <<  ?   << x << endl;    int ret; cin >> ret;    return ret;   }      int32_t main(){    cin >> n >> k;    int i=0, j=0, x;    int lo, hi;    while(1){     x = q(j);     if(x > k){lo = j-i-i, hi = j; break;}     if(x < k){lo = j, hi = j+i+i; break;}     j += i; ++i;    }    while(lo <= hi){     int mid = (lo+hi)/2;     int x = q(mid);     if(x == k){      cout <<  !   << mod(mid) + 1 << endl;      exit(0);     }     if(x < k) lo = mid+1;     else hi = mid-1;    }   }   