#include <bits/stdc++.h>
using namespace std;
const int N = 300300;
int n, q;
char s[N];
int t[N << 2];
#define md ((l + r) >> 1)
void modify(int v, int l, int r, int p) {
if (l == r) {
t[v] ^= 1;
return;
}
if (p <= md) modify(v << 1, l, md, p);
else modify(v << 1 | 1, md + 1, r, p);
t[v] = t[v << 1] + t[v << 1 | 1];
}
int lg[N], rg[N];
int findL(int v, int l, int r, int p) {
if (l > p || t[v] == r - l + 1) {
return -1;
}
if (l == r) return l;
int ans = findL(v << 1 | 1, md + 1, r, p);
if (ans == -1) ans = findL(v << 1, l, md, p);
return ans;
}
int findR(int v, int l, int r, int p) {
if (r < p || t[v] == r - l + 1) {
return -1;
}
if (l == r) return l;
int ans = findR(v << 1, l, md, p);
if (ans == -1) ans = findR(v << 1 | 1, md + 1, r, p);
return ans;
}
int get(int v, int l, int r, int L, int R) {
if (L <= l && r <= R) {
return t[v];
}
int ans = 0;
if (L <= md) ans += get(v << 1, l, md, L, R);
if (md < R) ans += get(v << 1 | 1, md + 1, r, L, R);
return ans;
}
#undef md
vector<int> ps[N];
vector<int> ft[N];
void fake_add(int x, int y) {
// printf("add %d %d\n", x, y);
if (x > n || y > n) return;
for (; x <= n; x += x & -x) {
ps[x].push_back(y);
}
}
void fake_get(int x, int y) {
for (; x > 0; x -= x & -x) {
ps[x].push_back(y);
}
}
void build() {
for (int x = 1; x <= n; ++x) {
sort(ps[x].begin(), ps[x].end());
ps[x].resize(unique(ps[x].begin(), ps[x].end()) - ps[x].begin());
/*
printf("at %d: ", x);
for (int y : ps[x]) {
printf("%d ", y);
}
puts("");
*/
ft[x].assign(ps[x].size() + 1, 0);
}
}
void add(int x, int y, int val) {
if (x > n || y > n) return;
// printf("%d %d\n", x, y);
for (; x <= n; x += x & -x) {
int yy = upper_bound(ps[x].begin(), ps[x].end(), y) - ps[x].begin();
// printf("%d %d\n", x, y);
for (; yy < ft[x].size(); yy += yy & -yy) {
ft[x][yy] += val;
}
}
}
int get(int x, int y) {
int ans = 0;
for (; x > 0; x -= x & -x) {
int yy = upper_bound(ps[x].begin(), ps[x].end(), y) - ps[x].begin();
for (; yy > 0; yy -= yy & -yy) {
ans += ft[x][yy];
}
}
return ans;
}
int lq[N], rq[N];
int ans[N];
int vq[N];
int pq[N];
int main() {
scanf("%d %d %s", &n, &q, s + 1);
for (int i = 1; i <= n; ++i) {
if (s[i] == '1') {
modify(1, 1, n, i);
}
}
for (int i = 1; i <= q; ++i) {
char buf[10];
scanf("%s", buf);
if (buf[0] == 'q') {
scanf("%d %d", lq + i, rq + i);
--rq[i];
if (get(1, 1, n, lq[i], rq[i]) == rq[i] - lq[i] + 1) {
ans[i] = i;
}
// printf("%d %d\n", lq[i], rq[i]);
fake_get(lq[i], rq[i]);
} else {
int p;
scanf("%d", &p);
lg[i] = findL(1, 1, n, p - 1);
if (lg[i] == -1) {
lg[i] = 1;
} else {
lg[i]++;
}
rg[i] = findR(1, 1, n, p + 1);
if (rg[i] == -1) {
rg[i] = n;
} else {
--rg[i];
}
// printf("%d %d\n", lg[i], rg[i]);
int v = (s[p] == '1' ? i : -i);
s[p] = '0' + '1' - s[p];
fake_add(lg[i], p);
fake_add(lg[i], rg[i] + 1);
fake_add(p + 1, p);
fake_add(p + 1, rg[i] + 1);
modify(1, 1, n, p);
vq[i] = v;
pq[i] = p;
}
}
build();
// return 0;
for (int i = 1; i <= q; ++i) {
if (lq[i]) {
// query
ans[i] += get(lq[i], rq[i]);
printf("%d\n", ans[i]);
} else {
int v = vq[i];
int p = pq[i];
add(lg[i], p, v);
add(lg[i], rg[i] + 1, -v);
add(p + 1, p, -v);
add(p + 1, rg[i] + 1, v);
}
}
}
