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| #include <cstdio> #include <queue> #include <cstring> #include <algorithm> using namespace std; template <class Type> void read (Type &x) { char c; bool flag = false; while ((c = getchar()) < '0' || c > '9') c == '-' && (flag = true); x = c - '0'; while ((c = getchar()) >= '0' && c <= '9') x = (x << 1) + (x << 3) + c - '0'; flag && (x = ~x + 1); } template <class Type, class ...rest> void read (Type &x, rest &...y) { read(x), read(y...); } template <class Type> void write (Type x) { x < 0 && (putchar('-'), x = ~x + 1); x > 9 && (write(x / 10), 0); putchar('0' + x % 10); } typedef long long LL; const int N = 5e4 + 10; struct PAM { char str[N]; int n, cnt, last; struct Node { int p, len, s, nxt[26]; } tr[N]; int get (int x, int t) { while (str[t - 1 - tr[x].len] != str[t]) x = tr[x].p; return x; } void build() { scanf("%s", str + 1); str[0] = '$'; n = strlen(str + 1); tr[0].p = 1, tr[1].len = -1; last = 0, cnt = 2; for (int i = 1; i <= n; ++i) { int c = str[i] - 'A', p = get(last, i); if (!tr[p].nxt[c]) { int q = cnt++; tr[q].len = tr[p].len + 2; tr[q].p = tr[get(tr[p].p, i)].nxt[c]; tr[p].nxt[c] = q; } ++tr[last = tr[p].nxt[c]].s; } for (int i = cnt - 1; i > 1; --i) tr[tr[i].p].s += tr[i].s; tr[0].s = tr[1].s = 0; } } A, B; LL ans; void dfs (int x, int y) { ans += (LL)A.tr[x].s * B.tr[y].s; for (int i = 0; i < 26; ++i) if (A.tr[x].nxt[i] && B.tr[y].nxt[i]) dfs(A.tr[x].nxt[i], B.tr[y].nxt[i]); } int main () { A.build(), B.build(); dfs(1, 1), dfs(0, 0); write(ans); return 0; }
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