diff --git a/Luogu/P1758/P1758.cpp b/Luogu/P1758/P1758.cpp new file mode 100644 index 00000000..599f3e93 --- /dev/null +++ b/Luogu/P1758/P1758.cpp @@ -0,0 +1,58 @@ +#include +#include +#include +#include + +using std::cin; +using std::cout; +const char endl = '\n'; + +const int N = 505; +const int mod = 1024523; + +int n, m, f[2][N][N]{1}; +std::string a, b; + +int main() { + std::ios::sync_with_stdio(false); + cin.tie(nullptr); + + cin >> n >> m >> a >> b; + + std::reverse(a.begin(), a.end()); + std::reverse(b.begin(), b.end()); + + a = ' ' + a; + b = ' ' + b; + + for (int k = 1; k <= n + m; k++) { + int t = k & 1, + p = t ^ 1; + + memset(f[t], 0x00, sizeof(f[t])); + + for (int i = std::max(0, k - m); i <= std::min(n, k); i++) { + for (int j = std::max(0, k - m); j <= std::min(n, k); j++) { + if (i && j && a[i] == a[j]) { + f[t][i][j] = (f[t][i][j] + f[p][i - 1][j - 1]) % mod; + } + + if (i && k - j && a[i] == b[k - j]) { + f[t][i][j] = (f[t][i][j] + f[p][i - 1][j]) % mod; + } + + if (k - i && j && b[k - i] == a[j]) { + f[t][i][j] = (f[t][i][j] + f[p][i][j - 1]) % mod; + } + + if (k - i && k - j && b[k - i] == b[k - j]) { + f[t][i][j] = (f[t][i][j] + f[p][i][j]) % mod; + } + } + } + } + + cout << f[(n + m) & 1][n][n] << endl; + + return 0; +}