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49 lines
840 B
C++
49 lines
840 B
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 = 1e6 + 5;
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const int mod = 1e9 + 7;
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int n;
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long long f[N], ans;
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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;
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if (n == 1) {
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cout << 1 << endl;
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exit(0);
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}
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f[1] = 1;
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for (int j = 1; j < n; j++) {
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if (j <= 3) {
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for (int i = j + 1; i < n; i++) {
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f[i] = (f[i] + f[j]) % mod;
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}
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} else {
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for (int k = -1; k <= 1; k++) {
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for (int i = j + k; i < n; i += j) {
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if (j < i) f[i] = (f[i] + f[j]) % mod;
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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 < n; i++) {
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ans = (ans + f[i]) % mod;
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}
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cout << ans * n % mod << endl;
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return 0;
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}
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