#pragma GCC optimize("Ofast")
#include <bits/stdc++.h>
using namespace std;
// clang-format off
namespace io {
const int __SIZE = (1 << 21) + 1;
char ibuf[__SIZE], *iS, *iT, obuf[__SIZE], *oS = obuf, *oT = oS + __SIZE - 1, __c, qu[55]; int __f, qr, _eof;
#define Gc() (iS == iT ? (iT = (iS = ibuf) + fread (ibuf, 1, __SIZE, stdin), (iS == iT ? EOF : *iS ++)) : *iS ++)
inline void flush () { fwrite (obuf, 1, oS - obuf, stdout), oS = obuf; }
inline void gc (char &x) { x = Gc(); }
inline void pc (char x) { *oS ++ = x; if (oS == oT) flush (); }
inline void pstr (const char *s) { int __len = strlen(s); for (__f = 0; __f < __len; ++__f) pc (s[__f]); }
inline void gstr (char *s) { for(__c = Gc(); __c < 32 || __c > 126 || __c == ' ';) __c = Gc();
for(; __c > 31 && __c < 127 && __c != ' '; ++s, __c = Gc()) *s = __c; *s = 0; }
template <class I> inline bool gi (I &x) { _eof = 0;
for (__f = 1, __c = Gc(); (__c < '0' || __c > '9') && !_eof; __c = Gc()) { if (__c == '-') __f = -1; _eof |= __c == EOF; }
for (x = 0; __c <= '9' && __c >= '0' && !_eof; __c = Gc()) x = x * 10 + (__c & 15), _eof |= __c == EOF; x *= __f; return !_eof; }
template <class I> inline void print (I x) { if (!x) pc ('0'); if (x < 0) pc ('-'), x = -x;
while (x) qu[++ qr] = x % 10 + '0', x /= 10; while (qr) pc (qu[qr --]); }
struct Flusher_ {~Flusher_(){flush();}}io_flusher_;
} using io::pc; using io::gc; using io::pstr; using io::gstr; using io::gi; using io::print;
// clang-format on
#define all(a) a.begin(), a.end()
#define fi first
#define se second
#define pb push_back
#define mp make_pair
using ll = long long;
using pii = pair<int, int>;
//#define int ll
const int MOD = 1000000007;
int n;
int trr[300005];
struct lin {
int k, b;
const lin operator+(const lin &o) const { return {k + o.k, b + o.b}; }
} s[15 << 20];
int lc[15 << 20], rc[15 << 20];
int _stt = 1;
void modif(int &idx, int u, lin d, int l = 0, int r = n + 1) {
if (!(l <= u && u < r))
return;
if (!idx)
idx = _stt++;
if (r - l == 1) {
s[idx] = s[idx] + d;
return;
}
modif(lc[idx], u, d, l, (l + r) / 2);
modif(rc[idx], u, d, (l + r) / 2, r);
s[idx] = s[lc[idx]] + s[rc[idx]];
}
lin nsbasket(int idx, int L, int R, int l = 0, int r = n + 1) {
if (!idx || R <= l || r <= L)
return {0, 0};
if (L <= l && r <= R)
return s[idx];
return nsbasket(lc[idx], L, R, l, (l + r) / 2) +
nsbasket(rc[idx], L, R, (l + r) / 2, r);
}
void add(int i, int j, lin r) {
i++;
while (i <= n + 2) {
modif(trr[i], j, r);
i += (i & (-i));
}
}
lin qry(int i, int j) {
i++;
lin ans = {0, 0};
while (i) {
ans = ans + nsbasket(trr[i], 0, j + 1);
i -= (i & (-i));
}
return ans;
}
int T;
void toggle(int l, int r, int f) {
if (l > r)
return;
lin yes = {1, -T}, no = {-1, T};
if (f == -1)
swap(yes, no);
add(l, l, yes), add(l, r + 1, no), add(r + 1, l, no), add(r + 1, r + 1, yes);
}
signed main() {
ios_base::sync_with_stdio(false);
cin.tie(0);
int q;
gi(n), gi(q);
static char s[300005];
gstr(s);
set<int> zp;
zp.insert(-1), zp.insert(n);
for (int i = 0; i < n; i++)
if (s[i] == '0')
zp.insert(i);
{
auto s = zp.begin();
while (s != zp.end()) {
if (*s != -1)
toggle(*prev(s) + 1, *s - 1, 1);
s = next(s);
}
}
for (T = 1; T <= q; T++) {
gstr(s);
if (s[0] == 't') {
int i;
gi(i);
auto q = zp.find(--i);
if (q != zp.end()) {
toggle(*prev(q) + 1, i - 1, -1);
toggle(i + 1, *next(q) - 1, -1);
toggle(*prev(q) + 1, *next(q) - 1, 1);
zp.erase(q);
} else {
q = zp.insert(i).first;
toggle(*prev(q) + 1, *next(q) - 1, -1);
toggle(*prev(q) + 1, i - 1, 1);
toggle(i + 1, *next(q) - 1, 1);
}
} else {
int l, r;
gi(l), gi(r);
lin ans = qry(l - 1, r - 2);
print(T * ans.k + ans.b), pc('\n');
}
}
}
