#include <iostream>
#include <bits/stdc++.h>
using namespace std;
#define lli long long int
#define debug(a) cout << #a << " = " << a << endl
#define debugsl(a) cout << #a << " = " << a << ", "
#define rep(i,a,b) for(int i = (a); i <= (b); i++)
#define repa(i,a,b) for(int i = (a); i >= (b); i--)
#define MAX 300000
#define ini first.first
#define t first.second
#define f second
#define fin second.first
#define tiempo second.second
lli n,q,last,a,b,dif;
string st,com;
set<pair< pair<lli,lli> ,lli> > rangos;
set<pair< pair<lli,lli> ,lli> >::iterator l,r;
pair< pair<lli,lli> ,lli> ran,x;
lli bit[MAX+2],res[MAX+2];
//inicio, tipo, final tiempo
vector< pair< pair<lli,lli>, pair<lli,lli> > > orden;
void update(lli pos, lli val) {
while (pos <= n) {
bit[pos] += val;
pos += pos&(-pos);
}
return;
}
lli acumula(lli pos) {
lli res = 0;
while (pos > 0) {
res += bit[pos];
pos -= pos&(-pos);
}
return pos;
}
int main()
{
ios_base::sync_with_stdio(false);
cin.tie(NULL);
cin >> n >> q;
cin >> st;
st = '0' + st + '0';
//inicializar en base al string
last = -1;
rep(i,1,n) {
if (st[i] == '0') {
if (last != -1) rangos.insert({{last,0},i-1});
last = -1;
}
else if (last == -1) last = i;
}
//todos los toggle events suceden primero
rep(Q,1,q) {
res[Q] = -1;
cin >> com >> a;
if (com[0] == 't') {
if (st[a] == '0') {
//creo, uno o agrando
if (st[a+1] == '1') {
if (st[a-1] == '1') {
//unir ambos ragos
l = rangos.upper_bound({{a+1,0},0});
r = l;
l--;
x.f = (*r).f;
x.ini = (*l).ini;
x.t = Q;
ran = (*l);
dif = Q - ran.t;
orden.push_back({{ran.ini,-1},{ran.f,dif}});
ran = (*r);
dif = Q - ran.t;
orden.push_back({{ran.ini,-1},{ran.f,dif}});
rangos.erase(l);
rangos.erase(r);
rangos.insert(x);
}
else {
//solo derecha
r = rangos.upper_bound({{a+1,0},0});
x.f = (*r).f;
x.ini = a;
x.t = Q;
ran = (*r);
dif = Q - ran.t;
orden.push_back({{ran.ini,-1},{ran.f,dif}});
rangos.erase(r);
rangos.insert(x);
}
}
else if (st[a-1] == '1') {
//solo izqueireda
l = rangos.upper_bound({{a+1,0},0});
l--;
x.f = a;
x.ini = (*l).ini;
x.t = Q;
ran = (*l);
dif = Q - ran.t;
orden.push_back({{ran.ini,-1},{ran.f,dif}});
rangos.erase(l);
rangos.insert(x);
}
else rangos.insert( {{a,Q},a });
st[a] = '1';
}
else {
// parte rango
r = rangos.upper_bound({{a+1,0},0});
r--;
ran = (*r);
rangos.erase(r);
dif = Q - ran.t;
orden.push_back({{ran.ini,-1},{ran.f,dif}});
if (st[a-1] == 1) rangos.insert({ {ran.ini,Q}, a-1});
if (st[a+1] == 1) rangos.insert({ {a+1, Q}, ran.f});
st[a] = '0';
}
}
else {
cin >> b;
b--;
//agrego los eventos y al final proceso
orden.push_back({ {a,Q},{b,Q}});
r = rangos.upper_bound({{a+1,0},0});
if (r != rangos.begin()) {
r--;
if ((*r).f >= b) res[Q] = Q - (*r).t;
}
}
}
sort(orden.begin(), orden.end());
for(auto act : orden) {
if (act.t == -1) update(act.fin,act.tiempo);
else {
a = acumula(n);
b = acumula(act.fin-1);
res[act.t] += a-b;
}
}
rep(i,1,q) if (res[i] > -1) cout << res[i] << "\n";
}
