//https://ncode.syosetu.com/n4830bu/263/ #include using namespace std; using ll = long long; struct PalindromicTree { PalindromicTree() { node* size_m1 = create_node(); size_m1->suffix_link = 0; size_m1->len = -1; node* size_0 = create_node(); size_0->suffix_link = 0; size_0->len = 0; active_idx = 0; } struct node { unordered_map link; int suffix_link, len, count; }; vector nodes; string S; int active_idx; node* create_node() { nodes.emplace_back(); node* ret = &nodes.back(); ret->count = 0; return ret; } int find_prev_palindromic_idx(int node_id) { const int pos = (int)S.size() - 1; while (true) { const int opposite_side_idx = pos - 1 - nodes[node_id].len; if (opposite_side_idx >= 0 && S[opposite_side_idx] == S.back()) break; node_id = nodes[node_id].suffix_link; } return node_id; } void add(char ch) { S += ch; const int prev = find_prev_palindromic_idx(active_idx); const auto inserted_result = nodes[prev].link.insert(make_pair(ch, (int)nodes.size())); active_idx = inserted_result.first->second; if (!inserted_result.second) { nodes[active_idx].count++; return; } node* new_node = create_node(); new_node->count = 1; new_node->len = nodes[prev].len + 2; if (new_node->len == 1) { new_node->suffix_link = 1; } else { new_node->suffix_link = nodes[find_prev_palindromic_idx(nodes[prev].suffix_link)].link[ch]; } } vector build_frequency() { vector frequency(nodes.size()); for (int i = (int)nodes.size() - 1; i > 0; i--) { frequency[i] += nodes[i].count; frequency[nodes[i].suffix_link] += frequency[i]; } return frequency; } }; int main() { string S, T; cin >> S >> T; string ST = S + "#$" + T; auto maine = [&](string S) { PalindromicTree book; for (auto&& c : S) { book.add(c); } auto frequency = book.build_frequency(); ll ret = 0; for (int i = 2; i < frequency.size(); i++) { ret += 1ll * frequency[i] * (frequency[i] - 1) / 2; } return ret; }; cout << maine(ST) - maine(S) - maine(T) << endl; }