/*************************************
* author: marvinthang *
* created: 10.11.2023 08:32:34 *
*************************************/
#include <bits/stdc++.h>
using namespace std;
#define fi first
#define se second
#define left ___left
#define right ___right
#define TIME (1.0 * clock() / CLOCKS_PER_SEC)
#define MASK(i) (1LL << (i))
#define BIT(x, i) ((x) >> (i) & 1)
#define __builtin_popcount __builtin_popcountll
#define ALL(v) (v).begin(), (v).end()
#define REP(i, n) for (int i = 0, _n = (n); i < _n; ++i)
#define REPD(i, n) for (int i = (n); i-- > 0; )
#define FOR(i, a, b) for (int i = (a), _b = (b); i < _b; ++i)
#define FORD(i, b, a) for (int i = (b), _a = (a); --i >= _a; )
#define FORE(i, a, b) for (int i = (a), _b = (b); i <= _b; ++i)
#define FORDE(i, b, a) for (int i = (b), _a = (a); i >= _a; --i)
#define scan_op(...) istream & operator >> (istream &in, __VA_ARGS__ &u)
#define print_op(...) ostream & operator << (ostream &out, const __VA_ARGS__ &u)
#ifdef LOCAL
#include "debug.h"
#else
#define file(name) if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
#define DB(...) 23
#define db(...) 23
#define debug(...) 23
#endif
template <class U, class V> scan_op(pair <U, V>) { return in >> u.first >> u.second; }
template <class T> scan_op(vector <T>) { for (size_t i = 0; i < u.size(); ++i) in >> u[i]; return in; }
template <class U, class V> print_op(pair <U, V>) { return out << '(' << u.first << ", " << u.second << ')'; }
template <size_t i, class T> ostream & print_tuple_utils(ostream &out, const T &tup) { if constexpr(i == tuple_size<T>::value) return out << ")"; else return print_tuple_utils<i + 1, T>(out << (i ? ", " : "(") << get<i>(tup), tup); }
template <class ...U> print_op(tuple<U...>) { return print_tuple_utils<0, tuple<U...>>(out, u); }
template <class Con, class = decltype(begin(declval<Con>()))> typename enable_if <!is_same<Con, string>::value, ostream&>::type operator << (ostream &out, const Con &con) { out << '{'; for (__typeof(con.begin()) it = con.begin(); it != con.end(); ++it) out << (it == con.begin() ? "" : ", ") << *it; return out << '}'; }
// index from 0
template <class T> struct Fenwick {
int n; vector <T> bit;
Fenwick(int _n = 0): n(_n), bit(n + 1, 0) {}
void reset(void) { fill(bit.begin(), bit.end(), 0); }
void resize(int _n) { bit.assign(_n + 1, 0); }
void update(int i, T val) { for (++i; i <= n; i += i & -i) bit[i] += val; }
T get(int i) {
if (i < 0) return 0;
T res(0);
for (i = min(i + 1, n); i > 0; i &= i - 1) res += bit[i];
return res;
}
int upper_bound(T val) {
int res = 0;
for (int i = __lg(n); i >= 0; --i)
if ((res | MASK(i)) <= n && val >= bit[res | MASK(i)]) res |= MASK(i), val -= bit[res];
return res;
}
int lower_bound(T val) {
int res = 0;
for (int i = __lg(n); i >= 0; --i)
if ((res | MASK(i)) <= n && val > bit[res | MASK(i)]) res |= MASK(i), val -= bit[res];
return res;
}
};
// end of template
void process(void) {
int n, q; string s; cin >> n >> q >> s;
map <int, int> mp;
vector <array<int, 3>> queries(q);
REP(i, q) {
string s; cin >> s >> queries[i][1];
queries[i][0] = s[0] == 'q';
--queries[i][1];
if (queries[i][0]) {
cin >> queries[i][2];
queries[i][2] -= 2;
}
}
Fenwick <long long> bit_sum(n);
Fenwick <int> bit_cnt(n);
vector <long long> sum(q);
vector <bool> exist(q);
function <vector <array <int, 3>>(int, int, const vector <int> &)> solve = [&] (int l, int r, const vector <int> &ask) {
if (r - l == 1) {
vector <array <int, 3>> events;
auto addEvent = [&] (int x, int y, int v) {
events.insert(lower_bound(ALL(events), array{x, y, v}), array{x, y, v});
};
if (!l) {
REP(i, n) if (s[i] == '1') {
int j = i;
while (j < n && s[i] == s[j]) ++j;
mp[i] = j;
events.push_back(array{i, j, 1});
if (queries[l][0] && i <= queries[l][1] && queries[l][2] < j) sum[l] = 1;
i = j;
}
REP(i, n) if (s[i] == '1') bit_cnt.update(i, +1);
}
if (!queries[l][0]) {
int u = queries[l][1];
if (s[u] == '0') {
auto it = mp.lower_bound(u);
int r = u + 1;
if (u + 1 < n && s[u + 1] == '1') {
r = it->se;
addEvent(u + 1, r, l);
it = mp.erase(it);
}
if (u && s[u - 1] == '1') {
it = prev(it);
addEvent(it->fi, it->se, l);
it->se = r;
addEvent(it->fi, it->se, -l);
} else {
mp[u] = r;
addEvent(u, r, -l);
}
s[u] = '1';
bit_cnt.update(u, +1);
} else {
auto it = prev(mp.upper_bound(u));
addEvent(it->fi, it->se, l);
if (u + 1 < it->se) {
mp[u + 1] = it->se;
addEvent(u + 1, it->se, -l);
}
if (it->fi < u) {
it->se = u;
addEvent(it->fi, u, -l);
} else mp.erase(it);
s[u] = '0';
bit_cnt.update(u, -1);
}
} else {
int x = queries[l][1], y = queries[l][2];
exist[l] = bit_cnt.get(y) - bit_cnt.get(x - 1) == y - x + 1;
}
return events;
}
int m = l + r >> 1;
vector <int> ask_left, ask_right;
for (int i: ask) (i < m ? ask_left : ask_right).push_back(i);
auto left = solve(l, m, ask_left);
int j = 0;
for (int i: ask_right) {
while (j < left.size() && left[j][0] <= queries[i][1]) {
bit_sum.update(left[j][0], left[j][2]);
bit_sum.update(left[j][1], -left[j][2]);
++j;
}
sum[i] += bit_sum.get(queries[i][2]);
}
while (j--) {
bit_sum.update(left[j][0], -left[j][2]);
bit_sum.update(left[j][1], left[j][2]);
}
auto right = solve(m, r, ask_right);
vector <array <int, 3>> events;
merge(ALL(left), ALL(right), back_inserter(events));
return events;
};
vector <int> ask;
REP(i, q) if (queries[i][0]) ask.push_back(i);
sort(ALL(ask), [&] (int a, int b) { return queries[a][1] < queries[b][1]; });
solve(0, q, ask);
REP(i, q) if (queries[i][0]) cout << exist[i] * i + sum[i] << '\n';
}
int main(void) {
ios_base::sync_with_stdio(false); cin.tie(nullptr); // cout.tie(nullptr);
file("street_lamps");
// int t; cin >> t; while (t--)
process();
// cerr << "Time elapsed: " << TIME << " s.\n";
return (0^0);
}
