//#define NDEBUG
#include <bits/stdc++.h>
#include <bits/extc++.h>
#define StarBurstStream ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
#define iter(a) a.begin(), a.end()
#define riter(a) a.rbegin(), a.rend()
#define lsort(a) sort(iter(a))
#define gsort(a) sort(riter(a))
#define pb(a) push_back(a)
#define eb(a) emplace_back(a)
#define pf(a) push_front(a)
#define pob pop_back()
#define pof pop_front()
#define mp(a, b) make_pair(a, b)
#define F first
#define S second
#define mt make_tuple
#define gt(t, i) get<i>(t)
#define iceil(a, b) ((a + b - 1) / b)
#define tomax(a, b) (a = max(a, b))
#define printv(a, b) {bool pvaspace=false; \
for(auto pva : a){ \
if(pvaspace) b << " "; pvaspace=true;\
b << pva;\
}\
b << "\n";}
//#define TEST
using namespace std;
using namespace __gnu_pbds;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
using pdd = pair<ld, ld>;
using tiii = tuple<int, int, int>;
const ll MOD = 1000000007;
const ll MAX = 2147483647;
template<typename A, typename B>
ostream& operator<<(ostream& o, pair<A, B> p){
return o << '(' << p.F << ',' << p.S << ')';
}
int main(){
StarBurstStream
int n, q;
cin >> n >> q;
string s;
cin >> s;
vector<int> o(n, q);
for(int i = 0; i < n; i++){
if(s[i] == '1') o[i] = -1;
}
vector<pair<int, pii>> qry;
for(int i = 0; i < q; i++){
string t;
cin >> t;
if(t == "toggle"){
int x;
cin >> x;
x--;
o[x] = i;
}
else{
int a, b;
cin >> a >> b;
a--; b -= 2;
qry.eb(mp(i, mp(a, b)));
}
}
vector<vector<int>> st(n, vector<int>(20));
for(int i = 0; i < n ;i++) st[i][0] = o[i];
for(int i = 1; i < 20; i++){
for(int j = 0; j + (1 << i) - 1 < n; j++){
st[j][i] = max(st[j][i - 1], st[j + (1 << (i - 1))][i - 1]);
}
}
for(auto i : qry){
int l = i.S.F, r = i.S.S;
int lg = __lg(r - l + 1);
int tmp = max(st[l][lg], st[r - (1 << lg) + 1][lg]);
cout << max(0, i.F - tmp) << "\n";
}
return 0;
}
