#include<bits/stdc++.h>
#define fi first
#define se second
#define endl "\n"
#define ii pair<int, int>
using namespace std;
const int N = 3e5 + 10;
int a[N], ans[N];
int n, q;
tuple<int, int, int> query[N];
pair<int, int> tt[N];
vector<int> node[N], bit[N];
void fakeup (int x, int y) {
for(x; x <= n; x += x & -x) node[x].push_back(y);
}
void up(int x, int yy, int val) {
for(x; x <= n; x += x & -x) {
for(int y = upper_bound(node[x].begin(), node[x].end(), yy) - node[x].begin(); y <= node[x].size(); y += y & -y) {
bit[x][y] += val;
}
}
}
int get(int x, int yy) {
int ret = 0;
for(x; x; x -= x & -x) {
for(int y = upper_bound(node[x].begin(), node[x].end(), yy) - node[x].begin(); y; y -= y & -y) {
ret += bit[x][y];
}
}
return ret;
}
void compress() {
for(int i = 1; i <= n; i++) {
sort(node[i].begin(), node[i].end());
node[i].resize(unique(node[i].begin(), node[i].end()) - node[i].begin());
bit[i].resize(node[i].size() + 1);
}
}
void fakeinc(int x, int y, int u, int v) {
fakeup(x, y);
fakeup(x, v + 1);
fakeup(u + 1, y);
fakeup(u + 1, v + 1);
}
void inc(int x, int y, int u, int v, int val) {
up(x, y, val);
up(x, v + 1, -val);
up(u + 1, y, -val);
up(u + 1, v + 1, val);
}
int main() {
#define task ""
cin.tie(0) -> sync_with_stdio(0);
if (fopen ("task.inp", "r")) {
freopen ("task.inp", "r", stdin);
freopen ("task.out", "w", stdout);
}
if (fopen (task".inp", "r")) {
freopen (task".inp", "r", stdin);
freopen (task".out", "w", stdout);
}
cin >> n >> q;
string str; cin >> str; str = " " + str;
set<int> s = {0, n + 1};
for(int i = 1; i <= n; i++) {
a[i] = str[i] - '0';
if (!a[i]) s.insert(i);
}
for(int timer = 1; timer <= q; timer++) {
string ask; cin >> ask;
if (ask[0] == 't') {
int i; cin >> i;
a[i] ^= 1;
if (a[i]) s.erase(s.find(i));
else s.insert(i);
auto it = s.upper_bound(i);
int r = *it - 1;
it--;
if (*it == i) it--;
int l = *it + 1;
fakeinc(l, i, i, r);
query[timer] = {0, l, r};
tt[timer].fi = i;
tt[timer].se = a[i] ? -timer : timer;
}
else {
int l, r; cin >> l >> r; r--;
query[timer] = {1, l, r};
if (*s.lower_bound(l) > r) ans[timer] += timer;
}
}
compress();
for(int timer = 1; timer <= q; timer++) {
int type, l, r; tie(type, l, r) = query[timer];
if (type == 0) {
int i, val; tie(i, val) = tt[timer];
inc(l, i, i, r, val);
}
else cout << get(l, r) + ans[timer] << endl;
}
}
