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49 lines
959 B
C++
49 lines
959 B
C++
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#include <iostream>
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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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int n, k;
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int cnt, r[2005], s[2005];
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long long f[15][2005][105], ans;
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void dfs(int x, int sum, int len) {
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if (len >= n) {
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r[++cnt] = x;
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s[cnt] = sum;
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return;
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}
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dfs(x, sum, len + 1);
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dfs(x + (1 << len), sum + 1, len + 2);
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}
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int main() {
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std::ios::sync_with_stdio(false);
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cin >> n >> k;
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dfs(0, 0, 0);
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for (int i = 1; i <= cnt; i++) f[1][i][s[i]] = 1;
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for (int i = 2; i <= n; i++) {
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for (int j = 1; j <= cnt; j++) {
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for (int p = 1; p <= cnt; p++) {
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if ((r[j] & r[p]) || ((r[j] << 1) & r[p]) || (r[j] & (r[p] << 1))) continue;
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for (int l = k; l >= s[j]; l--) {
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f[i][j][l] += f[i - 1][p][l - s[j]];
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}
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}
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}
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}
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for (int i = 1; i <= cnt; i++) ans += f[n][i][k];
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cout << ans << endl;
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return 0;
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}
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