#include <bits/stdc++.h>
std::string process(std::string c, int k) {
// c[k] = 'R';
// std::vector<int> lr, rl;
// for (int i = 0; i < k; ++i) {
// if (c[i] == 'R') lr.push_back(i);
// }
// for (int i = k + 1; i < c.size(); ++i) {
// if (c[i] == 'B') rl.push_back(i);
// }
// if (lr.size() >= rl.size()) {
// int k = rl.size();
// int pos = lr[lr.size() - k];
// for (int i = pos; i < c.size(); ++i) c[i] = 'B';
// } else {
// int k = lr.size();
// int pos = rl[k - 1];
// for (int i = 0; i <= pos; ++i) c[i] = 'R';
// }
// return c;
c[k] = 'R';
while (0 <= k && k < n) {
if (c[k] == 'R') {
c[k] = 'B';
k++;
} else {
c[k] = 'R';
k--;
}
}
return c;
}
int main() {
std::cin.tie(nullptr)->sync_with_stdio(false);
int n, m;
std::cin >> n >> m;
std::string c;
std::cin >> c;
std::vector<int> a(m);
for (auto& i : a) std::cin >> i, --i;
if (n <= 10) {
int st = 0;
for (int i = 0; i < n; ++i) {
st |= (c[i] == 'R') << i;
}
std::vector<std::vector<int>> ss(1 << n, std::vector<int>(n));
for (int mask = 0; mask < 1 << n; ++mask) {
for (int i = 0; i < n; ++i) {
int m4sk = mask;
int ptr = i;
m4sk |= 1 << i;
while (0 <= ptr && ptr < n) {
m4sk ^= 1 << ptr;
if (~m4sk >> ptr & 1) {
ptr++;
} else {
ptr--;
}
}
ss[mask][i] = m4sk;
}
}
std::vector<int> qq(1 << n, -1);
std::vector<int> pos(m, -1);
std::vector<int> leader(m, -1);
std::vector<std::vector<std::pair<int, int>>> que(m);
int q;
std::cin >> q;
std::vector<int> ans(q);
for (int i = 0; i < q; ++i) {
int l, r;
std::cin >> l >> r;
--l, --r;
que[r].emplace_back(l, i);
}
auto get = [&](int u) -> int {
while (u != leader[u]) u = leader[u] = leader[leader[u]];
return u;
};
for (int i = 0; i < m; ++i) {
if (qq[st] == -1) {
qq[st] = i;
pos[i] = st;
leader[i] = i;
} else {
leader[i] = qq[st];
}
std::vector<int> nw(1 << n, -1);
for (int j = 0; j < 1 << n; ++j) {
if (qq[j] == -1) continue;
int k = ss[j][a[i]];
if (nw[k] != -1) {
leader[qq[j]] = nw[k];
} else {
nw[k] = qq[j];
pos[qq[j]] = k;
}
}
qq = nw;
for (auto [l, id] : que[i]) {
ans[id] = __builtin_popcount(pos[get(l)]);
}
}
for (auto i : ans) std::cout << i << '\n';
} else {
int q;
std::cin >> q;
int l, r;
std::cin >> l >> r;
--l, --r;
for (int i = l; i <= r; ++i) {
c = process(c, a[i]);
}
std::cout << std::count(c.begin(), c.end(), 'R');
}
}
Compilation message
Main.cpp: In function 'std::string process(std::string, int)':
Main.cpp:23:30: error: 'n' was not declared in this scope
23 | while (0 <= k && k < n) {
| ^