#include <bits/stdc++.h>
using namespace std;
#define rep(i,s,e) for (int i = s; i <= e; ++i)
#define pb push_back
#define fi first
#define se second
#define len(a) (int)a.size()
typedef pair<int, int> ii;
typedef vector<ii> vii;
typedef vector<int> vi;
const int mx = 3e5;
int ans[mx+1], ft[mx+1];
vector<vi> g;
void upd (int x, int id) {
for (;id<=mx;id+=id&(-id)) ft[id] += x;
}
int qry (int id) {
int res = 0;
for (;id;id-=id&(-id)) res += ft[id];
return res;
}
void cdq (int l, int r) {
if (l==r) return;
int mid = (l+r)/2;
cdq (l, mid);
cdq (mid+1, r);
vii undo;
vector<vi> nxt;
int a = l, b = mid+1, k = l;
while (k<=r) {
if (a>mid || (b<=r && g[b]<g[a])) nxt.pb(g[b++]);
else nxt.pb(g[a++]);
++k;
}
rep (i,l,r) g[i] = nxt[i-l];
rep (i,l,r) {
int y = g[i][1], id = g[i][2], delt = g[i][3], t = g[i][4];
if (t>mid) ans[id] += qry(y);
else {
upd(delt,y);
undo.pb({delt,y});
}
}
for (ii el : undo) upd(-el.fi, el.se);
}
int main() {
ios::sync_with_stdio(0);
cin.tie(0);
int n, q; cin >> n >> q;
bool b[n+1];
string s; cin >> s;
set<int> st;
st.insert(0);
st.insert(n+1);
rep (i,1,n) {
b[i] = s[i-1]-'0';
if (!b[i]) st.insert(i);
}
vi get;
rep (i,1,q) {
string tp; cin >> tp;
int t = len(g);
if (tp[0]=='t') {
int u; cin >> u;
int prv = *--st.lower_bound(u)+1, nxt = *st.upper_bound(u)-1, c = 2*b[u]-1;
g.pb({prv,mx+1-nxt,0,c*i,t++});
if (u+1<=mx) g.pb({u+1,mx+1-nxt,0,-c*i,t++});
if (u-1>0) g.pb({prv,mx+1-(u-1),0,-c*i,t++});
if (b[u]) st.insert(u);
else st.erase(u);
b[u] ^= 1;
}
else {
int x, y; cin >> x >> y;
--y;
get.pb(i);
if (*st.lower_bound(x)>y) ans[i] += i;
g.pb({x,mx+1-y,i,0,t++});
}
}
cdq(0,len(g)-1);
for (int el : get) cout << ans[el] << "\n";
return 0;
}
