#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int,int> pi;
template <class T, class IndexType> struct OfflineSemiSparseFenwickTree2D {
static_assert(is_integral<IndexType>::value, "IndexType must be integeral");
int N; vector<int> st, cnt; vector<IndexType> inds; vector<T> BIT;
int getInd(int i, IndexType j) {
return upper_bound(inds.begin() + st[i], inds.begin() + st[i] + cnt[i], j)
- inds.begin() - st[i];
}
OfflineSemiSparseFenwickTree2D(int N,
vector<pair<int, IndexType>> updateInds)
: N(N), st(N + 1, 0), cnt(N + 1, 0) {
sort(updateInds.begin(), updateInds.end(),
[&] (const pair<int, IndexType> &a, const pair<int, IndexType> &b) {
return a.second < b.second;
});
vector<IndexType> last(N + 1, IndexType());
for (auto &&u : updateInds) for (int i = u.first + 1; i <= N; i += i & -i)
if (cnt[i] == 0 || u.second != last[i]) { cnt[i]++; last[i] = u.second; }
for (int i = 1; i <= N; i++) st[i] = st[i - 1] + cnt[i - 1];
inds.resize(st[N] + cnt[N]); BIT.resize(st[N] + cnt[N]);
fill(cnt.begin(), cnt.end(), 0); for (auto &&u : updateInds)
for (int i = u.first + 1; i <= N; i += i & -i)
if (cnt[i] == 0 || u.second != inds[st[i] + cnt[i] - 1])
inds[st[i] + cnt[i]++] = u.second;
}
void update(int i, IndexType j, T v) {
for (i++; i <= N; i += i & -i)
for (int s = st[i], c = cnt[i], y = getInd(i, j); y <= c; y += y & -y)
BIT[s + y - 1] += v;
}
T query(int d, IndexType r) {
T ret = T(); for (d++; d > 0; d -= d & -d)
for (int s = st[d], y = getInd(d, r); y > 0; y -= y & -y)
ret += BIT[s + y - 1];
return ret;
}
T query(int d, IndexType l, IndexType r) {
return query(d, r) - query(d, l - 1);
}
T query(int u, int d, IndexType l, IndexType r) {
return query(d, l, r) - query(u - 1, l, r);
}
};
int main(){
cin.tie(0)->sync_with_stdio(0);
int n,q; cin >> n >> q;
string s,ts; cin >> s;
ts = s;
vector<pi> upd_inds;
auto fake_upd = [&](int x1, int x2, int y1, int y2){
upd_inds.emplace_back(x2+1,y2+1);
upd_inds.emplace_back(x1,y1);
upd_inds.emplace_back(x2+1,y1);
upd_inds.emplace_back(x1,y2+1);
};
auto fake_add = [&](int l, int r){
fake_upd(l,r,l,r);
};
set<pi> in;
for(int i = 0; i < n; i++){
if(s[i] == '0') continue;
int ptr = i;
while(ptr < n && s[ptr] == '1') ptr++;
// all intervals (l,r) where i <= l,r < ptr will be affected
fake_add(i,ptr-1); in.insert({i,ptr-1});
i = ptr-1;
}
vector<array<int,3>> qu; vector<bool> sub(q);
for(int i = 0; i < q; i++){
string t; cin >> t;
if(t == "toggle"){
int x; cin >> x; x--;
qu.push_back({0,x,0});
if(s[x] == '0'){
// merge left and right intervals (if exists)
auto rit = in.lower_bound({x,-1});
int l = x, r = x; bool fl = 0;
if(rit != in.end() && rit->first == x+1){
r = rit->second; fl = 1; fake_add(rit->first,rit->second);
}
if(rit != in.begin()){
auto lft = rit; lft--;
if(lft->second == x-1){
l = lft->first;
fake_add(lft->first,lft->second);
in.erase(lft); }
}
if(fl){
// erase rit
in.erase(in.lower_bound({x,-1}));
}
in.insert({l,r});
fake_add(l,r);
} else{
auto cur = in.upper_bound({x,x});
if(cur == in.end() || cur->first > x || x > cur->second) cur--;
auto[l,r] = *cur;
assert(l <= x && x <= r);
in.erase(cur); fake_add(l,r);
if(l < x){
in.insert({l,x-1});
fake_add(l,x-1);
}
if(x < r){
in.insert({x+1,r});
fake_add(x+1,r);
}
}
s[x] = (s[x] == '0' ? '1' : '0');
} else{
int a,b; cin >> a >> b;
a--; b-=2;
qu.push_back({1,a,b}); bool fl = 0;
auto cur = in.upper_bound({a,a});
if(cur == in.end() || cur->first > a || a > cur->second){
if(cur == in.begin()) fl = 1;
else cur--;
}
if(!fl){
auto[l,r] = *cur;
if(l <= a && b <= r) sub[i] = 1;
} else sub[i] = 0;
}
}
s = ts; in.clear();
OfflineSemiSparseFenwickTree2D<int,int> ft(n+1,upd_inds);
auto upd = [&](int x1, int x2, int y1, int y2, int v){
ft.update(x2+1,y2+1,v);
ft.update(x1,y1,v);
ft.update(x2+1,y1,-v);
ft.update(x1,y2+1,-v);
};
for(int i = 0; i < n; i++){
if(s[i] == '0') continue;
int ptr = i;
while(ptr < n && s[ptr] == '1') ptr++;
// all intervals (l,r) where i <= l,r < ptr will be affected
upd(i,ptr-1,i,ptr-1,q); in.insert({i,ptr-1});
i = ptr-1;
}
for(int i = 0; i < q; i++){
auto add = [&](int l, int r){
upd(l,r,l,r,q-i-1);
};
auto rmv = [&](int l, int r){
upd(l,r,l,r,-(q-i-1));
};
if(qu[i][0] == 0){
int x = qu[i][1];
if(s[x] == '0'){
// merge left and right intervals (if exists)
auto rit = in.lower_bound({x,-1});
int l = x, r = x; bool fl = 0;
if(rit != in.end() && rit->first == x+1){
r = rit->second; fl = 1; rmv(rit->first,rit->second);
}
if(rit != in.begin()){
auto lft = rit; lft--;
if(lft->second == x-1){
l = lft->first;
rmv(lft->first,lft->second);
in.erase(lft); }
}
if(fl){
// erase rit
in.erase(in.lower_bound({x,-1}));
}
in.insert({l,r});
add(l,r);
} else{
auto cur = in.upper_bound({x,x});
if(cur == in.end() || cur->first > x || x > cur->second) cur--;
auto[l,r] = *cur;
assert(l <= x && x <= r);
in.erase(cur); rmv(l,r);
if(l < x){
in.insert({l,x-1});
add(l,x-1);
}
if(x < r){
in.insert({x+1,r});
add(x+1,r);
}
}
s[x] = (s[x] == '0' ? '1' : '0');
} else{
int a = qu[i][1],b = qu[i][2];
cout << ft.query(a,b)-sub[i]*(q-i-1) << "\n";
}
}
}
// x coordinate is left endpoint, y coordinate is right endpoint
