#include <bits/stdc++.h>
#define MAXN 100100

using namespace std;

struct Node {
    int ans;
    int cnt_0, cnt_1;
} V[4*MAXN][2]; // 0 - original, 1 - toggled

int n,m;
int in[MAXN];
int T[4*MAXN];

void build(int l, int r, int v) {
    if(l == r) {
        V[v][0].ans = 1;
        if(in[l] == 0) {
            V[v][0].cnt_0 = 1;
            V[v][0].cnt_1 = 0;
        } else {
            V[v][0].cnt_0 = 0;
            V[v][0].cnt_1 = 1;
        }
        V[v][1].ans = 1;
        V[v][1].cnt_0 = 1 - V[v][0].cnt_0;
        V[v][1].cnt_1 = 1 - V[v][0].cnt_1;
        return;
    }

    int mid = (l+r)>>1;
    build(l,mid, 2*v);
    build(mid+1, r, 2*v+1);
    V[v][0].cnt_0 = V[v*2][0].cnt_0 + V[v*2+1][0].cnt_0;
    V[v][0].cnt_1 = V[v*2][0].cnt_1 + V[v*2+1][0].cnt_1;
    V[v][1].cnt_0 = V[v*2][1].cnt_0 + V[v*2+1][1].cnt_0;
    V[v][1].cnt_1 = V[v*2][1].cnt_1 + V[v*2+1][1].cnt_1;

    V[v][0].ans = max(V[v*2][0].ans + V[v*2+1][0].cnt_1, V[v*2][0].cnt_0 + V[v*2+1][0].ans);
    V[v][1].ans = max(V[v*2][1].ans + V[v*2+1][1].cnt_1, V[v*2][1].cnt_0 + V[v*2+1][1].ans);
    cout<<l<<" "<<r<<" "<<v<<" "<<V[v][0].ans<<" "<<V[v*2][0].ans<<" "<<V[v*2+1][0].cnt_1<<endl;
}

void toggle(int l, int r, int v, int lll, int rrr) {
    if(lll <= l && rrr >= r) {
        swap(V[v][0], V[v][1]);
        T[v] = 1 - T[v];
        return;
    }

    int mid = (l+r)>>1;
    if(T[v] == 1) {
        swap(V[v*2][0], V[v*2][1]);
        T[v*2] = 1 - T[v*2];
        swap(V[v*2+1][0], V[v*2+1][1]);
        T[v*2+1] = 1 - T[v*2+1];
        T[v] = 0;
    }

    if(lll <= mid)
        toggle(l, mid, 2*v, lll, rrr);
    if(rrr > mid)
        toggle(mid+1, r, 2*v+1, lll, rrr);

    V[v][0].cnt_0 = V[v*2][0].cnt_0 + V[v*2+1][0].cnt_0;
    V[v][0].cnt_1 = V[v*2][0].cnt_1 + V[v*2+1][0].cnt_1;
    V[v][1].cnt_0 = V[v*2][1].cnt_0 + V[v*2+1][1].cnt_0;
    V[v][1].cnt_1 = V[v*2][1].cnt_1 + V[v*2+1][1].cnt_1;
    V[v][0].ans = max(V[v*2][0].ans + V[v*2+1][0].cnt_1, V[v*2][0].cnt_0 + V[v*2+1][0].ans);
    V[v][1].ans = max(V[v*2][1].ans + V[v*2+1][1].cnt_1, V[v*2][1].cnt_0 + V[v*2+1][1].ans);
}


int main() {
    cin>>n>>m;
    char ch;
    for(int i = 1; i <= n; ++i) {
        cin>>ch;
        if(ch == 0)
            in[i] = 0;
        else
            in[i] = 1;
    }

    build(1, n, 1);

    int type, l, r;
    for(int i = 0; i < m; ++i) {
        cin>>type;
        if(type == 1) {
            cout<<V[1][0].ans<<endl;
        } else {
            cin>>l>>r;
            toggle(1, n, 1, l, r);
        }
    }

    return 0;
}