#include<bits/stdc++.h>
using namespace std;
#define maxn 300005
#define fi first
#define se second
typedef pair<int,int> pii;
typedef vector<int> vi;
struct query{
int t,a,b,id,pt;
bool operator<(query o){
if(a!=o.a) return a>o.a;
else return t>o.t;
}
};
bool cmp(query x,query y){
if(x.b!=y.b) return x.b<y.b;
else return x.t>y.t;
}
struct segtre{
int tree[4*maxn],lazy[4*maxn];
void pushdown(int l,int r,int id){
if(lazy[id]==0) return;
int mid=(l+r)>>1,lz=lazy[id];lazy[id]=0;
lazy[id<<1]+=lz;lazy[id<<1|1]+=lz;
tree[id<<1]+=lz*(mid-l+1);tree[id<<1|1]+=lz*(r-mid);
}
int query(int l,int r,int id,int p){
if(l==r) return tree[id];
pushdown(l,r,id);
int mid=(l+r)>>1;
if(p<=mid) return query(l,mid,id<<1,p);
else return tree[id<<1]+query(mid+1,r,id<<1|1,p);
}
void update(int l,int r,int id,int tl,int tr,int val){
if(tr<l || r<tl) return;
if(tl<=l && r<=tr){
lazy[id]+=val;tree[id]+=val*(r-l+1);
return;
}
pushdown(l,r,id);
int mid=(l+r)>>1;
update(l,mid,id<<1,tl,tr,val);update(mid+1,r,id<<1|1,tl,tr,val);
tree[id]=tree[id<<1]+tree[id<<1|1];
}
}st;
map<pii,vector<int>> mp;
set<pii> s;
int n,q,f[maxn],ans[maxn],sz;
query que[maxn],qu[6*maxn];
//For each pair(l,r) find all time that l->r is all 1s and l-1,r+1 are 0s
void get(int p,int t){
if(f[p]==1){
pii x=*(--s.upper_bound({p,n+2}));
mp[x].push_back(t);s.erase(x);
if(x.first==p && x.second>p+1){
x.first++;s.insert(x);
mp[x].push_back(t);
}
else if(x.second==p+1 && x.first<p){
x.second--;s.insert(x);
mp[x].push_back(t);
}
else if(x.second>p+1 && p>x.first){
s.insert({x.first,p});mp[{x.first,p}].push_back(t);
s.insert({p+1,x.second});mp[{p+1,x.second}].push_back(t);
}
}
else{
if(f[p-1]==0 && f[p+1]==0){
s.insert({p,p+1});mp[{p,p+1}].push_back(t);
}
else if(f[p-1]==1 && f[p+1]==0){
pii x=*(--s.lower_bound({p,n}));
s.erase(x);mp[x].push_back(t);
s.insert({x.first,p+1});mp[{x.first,p+1}].push_back(t);
}
else if(f[p-1]==0 && f[p+1]==1){
pii x=*s.upper_bound({p,n});
s.erase(x);mp[x].push_back(t);
s.insert({p,x.second});mp[{p,x.second}].push_back(t);
}
else{
pii x1=*(--s.lower_bound({p,n})),x2=*s.upper_bound({p,n});
s.erase(x1);mp[x1].push_back(t);
s.erase(x2);mp[x2].push_back(t);
s.insert({x1.first,x2.second});mp[{x1.first,x2.second}].push_back(t);
}
}
f[p]^=1;
}
void dnc(int l,int r){
if(l==r) return;
int mid=(l+r)>>1;
dnc(l,mid);dnc(mid+1,r);
for(int i=l;i<=mid;i++) qu[i].pt=1;
for(int i=mid+1;i<=r;i++) qu[i].pt=2;
sort(qu+l,qu+r+1,cmp);
//cout << l << ' ' << r << '\n';
for(int i=r;i>=l;i--){
if(qu[i].pt==2 && qu[i].t==1){
int k=0,pre=0;
for(int x:mp[{qu[i].a,qu[i].b}]){
k++;
if(k&1) pre=x;
else{
st.update(1,q+1,1,pre,x-1,1);
}
}
}
else if(qu[i].pt==1 && qu[i].t==2) ans[qu[i].id]+=st.query(1,q+1,1,qu[i].id);
//cout << "{ " << qu[i].t << ' ' << qu[i].a << ' ' << qu[i].b << ' ' << qu[i].id << ' ' << qu[i].pt << ' ' << ans[qu[i].id] << "}\n";
}
for(int i=l;i<=r;i++){
if(qu[i].pt==2 && qu[i].t==1){
int k=0,pre=0;
for(int x:mp[{qu[i].a,qu[i].b}]){
k++;
if(k&1) pre=x;
else st.update(1,q+1,1,pre,x-1,-1);
}
}
}
}
//Main
signed main(){
ios_base::sync_with_stdio(false);
cin.tie(NULL);cout.tie(NULL);
cin >> n >> q;
int l=-1;
for(int i=1;i<=n;i++){
char c;cin >> c;
f[i]=c-'0';
if(f[i]==1){
if(l==-1) l=i;
}
else if(l!=-1){s.insert({l,i});l=-1;}
}
if(l!=-1) s.insert({l,n+1});
for(auto x:s) mp[x].push_back(1);
//for(pii x:s) cout << "{ " << x.first << ' ' << x.second << "} ";
//cout << '\n';
for(int i=1;i<=q;i++){
string ss;cin >> ss;
if(ss[0]=='t'){
que[i].t=1;que[i].id=i;
cin >> que[i].a;
get(que[i].a,i+1);
}
else{
que[i].t=2;que[i].id=i;
cin >> que[i].a >> que[i].b;
}
//for(pii x:s) cout << "{ " << x.first << ' ' << x.second << "} ";
//cout << '\n';
}
for(auto &x:mp){
qu[++sz]={1,x.fi.fi,x.fi.se,0,0};
if((int)x.second.size()&1) x.second.push_back(q+2);
//cout << x.fi.fi << '*' << x.fi.se << '\n';
//for(int v:x.second) cout << v << ' ';
//cout << '\n';
}
for(int i=1;i<=q;i++){
if(que[i].t==2) qu[++sz]=que[i];
}
sort(qu+1,qu+sz+1);
/*
for(int i=1;i<=sz;i++){
cout << "{ " << qu[i].t << ' ' << qu[i].a << ' ' << qu[i].b << ' ' << qu[i].id << ' ' << qu[i].pt << "}\n";
}
*/
dnc(1,sz);
for(int i=1;i<=q;i++){
if(que[i].t==2) cout << ans[i] << '\n';
}
}
