#include <bits/stdc++.h>
using namespace std;
using pii = pair<int,int>;
using pib = pair<int,bool>;
using ll = long long;
using pll = pair<ll,ll>;
using ld = long double;
#define all(x) (x).begin(),(x).end()
#ifdef fread_unlocked
#define fread fread_unlocked
#define fwrite fwrite_unlocked
#endif
#define lc ind<<1
#define rc ind<<1|1
const int MN = 3e5+4, MOD = 1e9+7, BASE = 31;
struct Q {
int x,y,t,full; //full is -1 if update
};
int ans[MN], bit[MN];
set<int> zeroes;
char s[10];
void update (int i, int v) {
for (;i<MN;i+=i&-i)
bit[i] += v;
}
int query (int i) {
int ret = 0;
for (;i;i^=i&-i)
ret += bit[i];
return ret;
}
void cdq (int l, int r, vector<Q> &queries) { //cdq over x
if (queries.empty()) return;
int mid = (l+r)/2;
vector<Q> lq,rq;
for (Q &q : queries) {
if (q.full == -1) {
if (q.x <= mid) update(q.y,q.t),lq.push_back(q);
else rq.push_back(q);
} else {
if (q.x <= mid && l != r) lq.push_back(q);
else ans[q.t] += query(q.y),rq.push_back(q);
}
}
for (Q &q : lq) if (q.full==-1) update(q.y,-q.t);
if (l<r) {
cdq(l,mid,lq); cdq(mid+1,r,rq);
}
}
int main () {
int n,q; char c; int a,b;
scanf ("%d %d",&n,&q);
vector<Q> queries;
zeroes.insert(0); zeroes.insert(n+1);
for (int i = 1; i <= n; i++) {
scanf (" %c",&c);
if (c == '0') zeroes.insert(i);
}
for (int i = 1; i <= q; i++) {
scanf (" %s %d",s,&a);
if (s[0] == 'q') {
scanf ("%d",&b); --b;
if (*zeroes.lower_bound(a) > b) ans[i] = i;
queries.push_back({a,b,i,0});
} else {
int cmpl = *prev(zeroes.lower_bound(a)) + 1;
int cmpr = *zeroes.upper_bound(a) - 1;
int sign = zeroes.count(a) ? -1 : 1;
queries.push_back({cmpl,a,i*sign,-1});
queries.push_back({cmpl,cmpr+1,i*-sign,-1});
queries.push_back({a+1,a,i*-sign,-1});
queries.push_back({a+1,cmpr+1,i*sign,-1});
if (sign > 0) zeroes.insert(a);
else zeroes.erase(a);
}
}
cdq(1,n,queries);
for (Q &qq : queries) if (!qq.full) printf ("%d\n",ans[qq.t]);
return 0;
}
/*
turn into 1:
update cmpl <= l <= i, i <= r <= cmpr with -t
turn into 0:
update cmpl <= l <= i, i <= r <= cmpr with t
query is point query
bit of a special case if it is currently all 1s, need to add current time
transform with 2d diff array since point update range query is nicer
turn into 1:
update (cmpl,i) with -t
update (cmpl,cmpr+1) with t
update (i+1,i) with t
update(i+1,cmpr+1) with -t
turn into 0:
update (cmpl,i) with t
update (cmpl,cmpr+1) with -t
update (i+1,i) with -t
update(i+1,cmpr+1) with t
query:
find sum with l <= L, r <= R
also add t+1 if currently intact
seems like easy cdq bash
*/
