// File C.cpp created on 01.02.2026 at 20:34:07
#include <bits/stdc++.h>
using i64 = long long;
#ifdef DEBUG
#include "/home/ahmetalp/Desktop/Workplace/debug.h"
#else
#define debug(...) void(23)
#endif
template<typename T>
struct fenwick {
std::vector<std::pair<int, T>> stk;
int n;
std::vector<T> tree;
fenwick(int n_) : n(n_), tree(n + 1) {}
void modify(int p, T x, bool flag = true) {
if (flag) {
stk.emplace_back(p, x);
}
for (p += 1; p <= n; p += p & -p) {
tree[p] += x;
}
}
void modify(int l, int r, T x, bool flag = true) {
modify(l, x, flag);
modify(r + 1, -x, flag);
}
T get(int p) {
T res = 0;
for (p += 1; p; p -= p & -p) {
res += tree[p];
}
return res;
}
T get(int l, int r) {
return get(r) - get(l - 1);
}
int snap() {
return int(stk.size());
}
void roll(int tim) {
while (snap() != tim) {
modify(stk.back().first, -stk.back().second, false);
stk.pop_back();
}
}
};
int main() {
std::ios::sync_with_stdio(false);
std::cin.tie(nullptr);
int N, Q;
std::cin >> N >> Q;
std::string S;
std::cin >> S;
S = "0" + S + "0";
N += 2;
std::set<int> bad;
std::vector<std::array<int, 5>> qrys;
for (int i = 0, j = 0; i < N; i = j) {
if (S[i] == '0') {
j += 1;
bad.emplace(i);
} else {
while (S[j + 1] == '1') {
j += 1;
}
qrys.push_back({1, i, j, 0, +1});
j += 1;
}
}
std::vector<std::array<i64, 2>> ans;
for (int j = 2; j <= Q + 1; ++j) {
std::string s;
std::cin >> s;
if (s[0] == 't') {
int i;
std::cin >> i;
if (S[i] == '0') {
bad.erase(i);
int l = *--bad.lower_bound(i);
int r = *bad.lower_bound(i);
qrys.push_back({j, l + 1, i - 1, 0, -1});
qrys.push_back({j, i + 1, r - 1, 0, -1});
qrys.push_back({j, l + 1, r - 1, 0, +1});
S[i] = '1';
} else {
int l = *--bad.lower_bound(i);
int r = *bad.lower_bound(i);
qrys.push_back({j, l + 1, i - 1, 0, +1});
qrys.push_back({j, i + 1, r - 1, 0, +1});
qrys.push_back({j, l + 1, r - 1, 0, -1});
bad.emplace(i);
S[i] = '0';
}
} else {
int l, r;
std::cin >> l >> r;
--r;
qrys.push_back({j, l, r, 1, ans.size()});
ans.push_back({0, j});
}
}
debug(qrys);
fenwick<i64> fen(N + 1);
auto aux = qrys;
auto dfs = [&](auto&& self, int l, int r) -> void {
if (l + 1 == r) {
return;
}
int mid = (l + r) >> 1;
self(self, l, mid);
self(self, mid, r);
int ptr0 = l;
int ptr1 = mid;
int snp = fen.snap();
int ptr = l;
while (ptr0 != mid && ptr1 != r) {
if (qrys[ptr0][1] <= qrys[ptr1][1]) {
if (qrys[ptr0][3] == 0) {
fen.modify(0, qrys[ptr0][2], qrys[ptr0][4] * qrys[ptr0][0]);
} else {
// ok
}
aux[ptr++] = qrys[ptr0++];
} else {
if (qrys[ptr1][3] == 0) {
// ok
} else {
ans[qrys[ptr1][4]][0] += fen.get(qrys[ptr1][2]);
}
aux[ptr++] = qrys[ptr1++];
}
}
while (ptr0 != mid) {
if (qrys[ptr0][3] == 0) {
fen.modify(0, qrys[ptr0][2], qrys[ptr0][4] * qrys[ptr0][0]);
} else {
// ok
}
aux[ptr++] = qrys[ptr0++];
}
while (ptr1 != r) {
if (qrys[ptr1][3] == 0) {
// ok
} else {
ans[qrys[ptr1][4]][0] += fen.get(qrys[ptr1][2]);
}
aux[ptr++] = qrys[ptr1++];
}
for (int i = l; i < r; ++i) {
qrys[i] = aux[i];
}
fen.roll(snp);
};
dfs(dfs, 0, int(qrys.size()));
for (int i = 0; i < int(ans.size()); ++i) {
i64 res = -ans[i][0];
if (res < 0) {
res += ans[i][1];
}
debug(ans[i]);
std::cout << res << '\n';
}
return 0;
}
