#include <bits/stdc++.h>
#define ll long long
#define INF 1000000005
#define MOD 1000000007
#define EPS 1e-10
#define rep(i,n) for(int i=0;i<(int)(n);++i)
#define rrep(i,n) for(int i=(int)(n)-1;i>=0;--i)
#define srep(i,s,t) for(int i=(int)(s);i<(int)(t);++i)
#define each(a,b) for(auto& (a): (b))
#define all(v) (v).begin(),(v).end()
#define len(v) (int)(v).size()
#define zip(v) sort(all(v)),v.erase(unique(all(v)),v.end())
#define cmx(x,y) x=max(x,y)
#define cmn(x,y) x=min(x,y)
#define fi first
#define se second
#define pb push_back
#define show(x) cout<<#x<<" = "<<(x)<<endl
#define spair(p) cout<<#p<<": "<<p.fi<<" "<<p.se<<endl
#define sar(a,n) cout<<#a<<":";rep(pachico,n)cout<<" "<<a[pachico];cout<<endl
#define svec(v) cout<<#v<<":";rep(pachico,v.size())cout<<" "<<v[pachico];cout<<endl
#define svecp(v) cout<<#v<<":";each(pachico,v)cout<<" {"<<pachico.first<<":"<<pachico.second<<"}";cout<<endl
#define sset(s) cout<<#s<<":";each(pachico,s)cout<<" "<<pachico;cout<<endl
#define smap(m) cout<<#m<<":";each(pachico,m)cout<<" {"<<pachico.first<<":"<<pachico.second<<"}";cout<<endl

using namespace std;

typedef pair<int,int> P;
typedef pair<ll,ll> pll;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<ll> vl;
typedef vector<vl> vvl;
typedef vector<double> vd;
typedef vector<P> vp;
typedef vector<string> vs;

const int MAX_N = 100005;

ll ad(ll x,ll y)
{
    return (x + y)%MOD;
}

class segtree{
private:
    int n,sz,cnt;
    vector<ll> node[2];
    ll mul[2][21];
    const ll add[2] = {1000010007, 1003333331};
    const ll mod[2] = {1000000007, 1000000009};
public:
    segtree(int ag){
        sz = ag;
        n = 1;
        cnt = 0;
        while(n < sz){
            cnt++;
            n *= 2;
        }
        mul[0][0] = mul[1][0] = 1;
        ll rr[2] = {10009+(((ll)&mul[0][0])>>5)%259, 10007+(((ll)&mul[1][0])>>5)%257};
        rep(i,2){
            rep(j,cnt){
                mul[i][j+1] = (mul[i][j] * rr[i]) % MOD;
            }
        }
        rep(i,2){
            node[i].resize(2*n-1);
        }
        rep(i,2){
            rep(j,sz){
                node[i][j+n-1] = add[i];
            }
        }
        rep(i,2){
            init(i,0,0);
        }
    }
    void init(int id, int index, int depth)
    {
        if(depth == cnt) return;
        init(id,2*index+1,depth+1);
        init(id,2*index+2,depth+1);
        node[id][index] = ad(mul[id][cnt-depth]*node[id][2*index+1]%MOD,node[id][2*index+2]);
    }
    void update(int k,ll a){
        a = (a+MOD)%MOD;
        int h = 1;
    	node[0][k] = ad(node[0][k],a), node[1][k] = ad(node[1][k],a);
    	while(k>0){
    		k = (k-1)/2;
            rep(i,2){
                node[i][k] = ad(mul[i][h++]*node[i][2*k+1]%MOD,node[i][2*k+2]);
            }
    	}
    }
    pll query(int a,int b,int dep=0,int k=0,int l=0,int r=-1){
        if(r < 0) r = n;
    	if(r <= a || b <= l){
    		return pll(0,0);
    	}
    	if(a <= l && r <= b){
    		return pll(node[0][k],node[1][k]);
    	}else{
    		pll vl = query(a,b,dep+1,2*k+1,l,(l+r)/2);
    		pll vr = query(a,b,dep+1,2*k+2,(l+r)/2,r);
    		return pll(ad(mul[0][cnt-dep]*vl.fi%MOD,vr.fi),ad(mul[1][cnt-dep]*vl.se%MOD,vr.se));
    	}
    }
};

map<pll,int> mp;

int main()
{
    cin.tie(0);
    ios::sync_with_stdio(false);
    int n,q;
    cin >> n >> q;
    segtree sg(n+1);
    mp[sg.query(0, n+1)] = 0;
    rep(i,q){
        string s;
        cin >> s;
        if(s == "!"){
            int a,b,c;
            cin >> a >> b >> c;
            sg.update(a,c);
            sg.update(b,-c);
            auto res = sg.query(0, n+1);
            if(mp.find(res) == mp.end()){
                mp[res] = i+1;
            }
        }else{
            cout << mp[sg.query(0, n+1)] << "\n";
        }
    }
    return 0;
}