#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
// typedef __uint128_t ll;

typedef int _loop_int;
#define REP(i,n) for(_loop_int i=0;i<(_loop_int)(n);++i)

#define DEBUG(x) cout<<#x<<": "<<x<<endl

#define CHMIN(a,b) a=min((a),(b))

const ll MOD = 281474976710597ll;
const ll BASE = 10009ll;

// const ll MOD = 9223372036854775783ll;
// const ll BASE = 1000000007ll;
// const ll C = 12525211ll;

int n,q;
char buf[25];
ll bpow[1252525];
ll bsum[1252525];

int main(){
  scanf("%d%d",&n,&q);
  
  bpow[0] = 1;
  REP(i,n)bpow[i+1] = BASE*bpow[i]%MOD;
  bsum[0] = 0;
  REP(i,n)bsum[i+1] = (bsum[i]+bpow[i])%MOD;

  map<ll,int> M;
  ll cur = 0;
  M[cur] = 0;
  REP(i,q){
    scanf("%s",buf);
    if(buf[0]=='!'){
      int l,r,k;
      scanf("%d%d%d",&l,&r,&k);
      ll v = (MOD+(bsum[r]-bsum[l]+MOD)%MOD*k%MOD)%MOD;
      cur = (cur + v)%MOD;
      if(!M.count(cur)){
        M[cur] = i+1;
      }
    }else{
      // query
      printf("%d\n",M[cur]);
    }
  }
  return 0;
}