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53 lines
1.0 KiB
C++
53 lines
1.0 KiB
C++
#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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const int N = 5e4 + 5,
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M = 205;
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const int mod = 1e9 + 7;
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int s[N][M], c[M][M];
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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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s[0][0] = s[1][1] = 1;
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for (int i = 2; i < N; i++) {
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s[i][1] = static_cast<long long>(s[i - 1][1]) * (i - 1) % mod;
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}
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for (int i = 2; i < N; i++) {
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for (int j = 1; j < M && j <= i; j++) {
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s[i][j] = (static_cast<long long>(s[i - 1][j - 1]) + static_cast<long long>(s[i - 1][j]) * (i - 1)) % mod;
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}
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}
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for (int i = 0; i < M; i++) {
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c[i][0] = c[i][i] = 1;
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}
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for (int i = 2; i < M; i++) {
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for (int j = 1; j < i; j++) {
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c[i][j] = (static_cast<long long>(c[i - 1][j]) + c[i - 1][j - 1]) % mod;
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}
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}
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int t;
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cin >> t;
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while (t--) {
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int n, a, b;
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cin >> n >> a >> b;
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cout << static_cast<long long>(s[n - 1][a + b - 2]) * c[a + b - 2][a - 1] % mod << endl;
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}
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return 0;
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}
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