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59 lines
1.3 KiB
C++
59 lines
1.3 KiB
C++
#include <iostream>
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#include <algorithm>
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#include <cstring>
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#include <string>
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using std::cin;
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using std::cout;
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const char endl = '\n';
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const int N = 505;
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const int mod = 1024523;
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int n, m, f[2][N][N]{1};
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std::string a, b;
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int main() {
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std::ios::sync_with_stdio(false);
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cin.tie(nullptr);
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cin >> n >> m >> a >> b;
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std::reverse(a.begin(), a.end());
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std::reverse(b.begin(), b.end());
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a = ' ' + a;
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b = ' ' + b;
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for (int k = 1; k <= n + m; k++) {
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int t = k & 1,
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p = t ^ 1;
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memset(f[t], 0x00, sizeof(f[t]));
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for (int i = std::max(0, k - m); i <= std::min(n, k); i++) {
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for (int j = std::max(0, k - m); j <= std::min(n, k); j++) {
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if (i && j && a[i] == a[j]) {
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f[t][i][j] = (f[t][i][j] + f[p][i - 1][j - 1]) % mod;
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}
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if (i && k - j && a[i] == b[k - j]) {
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f[t][i][j] = (f[t][i][j] + f[p][i - 1][j]) % mod;
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}
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if (k - i && j && b[k - i] == a[j]) {
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f[t][i][j] = (f[t][i][j] + f[p][i][j - 1]) % mod;
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}
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if (k - i && k - j && b[k - i] == b[k - j]) {
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f[t][i][j] = (f[t][i][j] + f[p][i][j]) % mod;
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}
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}
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}
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}
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cout << f[(n + m) & 1][n][n] << endl;
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return 0;
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}
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