#include "bits/stdc++.h"
using namespace std;
#ifdef Nero
#include "Deb.h"
#else
#define deb(...)
#endif
const int N = 3e5 + 5;
int n, q;
int tree[N];
vector<char> c;
vector<int> ans;
vector<array<int, 3>> qq;
vector<array<int, 3>> qu[N];
set<array<int, 3>> ranges;
void toggle(int ind, int t) {
if (c[ind] == '1') {
array<int, 3> key = {ind, n, n};
auto f = ranges.upper_bound(key);
--f;
auto [l, r, val] = *f;
if (l < ind) {
ranges.insert({l, ind - 1, t});
}
if (ind < r) {
ranges.insert({ind + 1, r, t});
}
qu[t].push_back({l, r, t - val});
ranges.erase(f);
} else {
bool pre = ind > 0 && c[ind - 1] == '1';
bool nx = ind < n - 1 && c[ind + 1] == '1';
if (nx && pre) {
array<int, 3> key = {ind, n, n};
auto f = ranges.upper_bound(key);
auto [l, r, val] = *f;
auto [ll, rr, vval] = *prev(f);
qu[t].push_back({l, r, t - val});
qu[t].push_back({ll, rr, t - val});
ranges.erase(prev(f));
ranges.erase(f);
ranges.insert({ll, r, t});
} else if (nx) {
array<int, 3> key = {ind, n, n};
auto f = ranges.upper_bound(key);
auto [l, r, val] = *f;
qu[t].push_back({l, r, t - val});
ranges.insert({ind, r, t});
ranges.erase(f);
} else if (pre) {
array<int, 3> key = {ind, n, n};
auto f = ranges.upper_bound(key);
--f;
auto [l, r, val] = *f;
qu[t].push_back({l, r, t - val});
ranges.insert({l, ind, t});
ranges.erase(f);
} else {
ranges.insert({ind, ind, t});
}
}
c[ind] ^= 1;
}
inline void upd (int id, int v) {
id++;
while (id < N) {
tree[id] += v;
id += id & -id;
}
}
inline long long qry (int id) {
id++;
long long ret = 0;
while (id) {
ret += tree[id];
id -= id & -id;
}
return ret;
}
int qry(int l, int r) {
return qry(r) - qry(l - 1);
}
void solve(int l, int r) {
if (l == r) {
return;
}
int mid = (l + r) / 2;
vector<array<int, 4>> t;
for (int i = l; i <= mid; ++i) {
for (auto [ll, rr, v] : qu[i]) {
t.push_back({ll, 0, rr, v});
}
}
for (int i = mid + 1; i <= r; ++i) {
auto [ll, rr, e] = qq[i];
if (e) {
t.push_back({ll, 1, rr, i});
}
}
//deb(l) deb(r) deb(t) cout << '\n';
sort(t.begin(), t.end());
for (int i = 0; i < (int) t.size(); ++i) {
auto [ll, tp, rr, val] = t[i];
if (tp == 0) {
upd(rr, val);
//deb(rr) deb(val) cout << '\n';
} else {
//deb(rr) deb(qry(rr, n)) cout << '\n';
ans[val] += qry(rr, n);
}
}
for (int i = 0; i < (int) t.size(); ++i) {
auto [ll, tp, rr, val] = t[i];
if (tp == 0) {
upd(rr, -val);
}
}
solve(l, mid);
solve(mid + 1, r);
}
int main(){
ios::sync_with_stdio(false);
cin.tie(nullptr);
cin >> n >> q;
c.resize(n);
for (int i = 0; i < n; ++i) {
cin >> c[i];
}
for (int i = 0; i < n; ++i) {
if (c[i] == '0') {
continue;
}
int j = i;
while (j + 1 < n && c[j + 1] == c[j]) {
j++;
}
ranges.insert({i, j, -1});
i = j;
}
qq.resize(q);
ans.resize(q);
for (int i = 0; i < q; ++i) {
string qt;
cin >> qt;
if (qt[0] == 'q') {
int x, y;
cin >> x >> y;
--x, y -= 2;
array<int, 3> key = {x, n, n};
auto f = ranges.upper_bound(key);
if (f != ranges.begin()) {
--f;
if ((*f)[1] >= y) {
ans[i] += i - (*f)[2];
}
}
qq[i] = {x, y, 1};
} else {
int ind;
cin >> ind;
toggle(ind - 1, i);
}
}
solve(0, q - 1);
for (int i = 0; i < q; ++i) {
if (qq[i][2] == 1) {
cout << ans[i] << '\n';
}
}
return 0;
}
