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#include "leetcode.h"
#define lli long long int
class Solution {
public:
int countOrders(int n) {
lli mod = 1e9 + 7;
vector<lli> dp(n + 2);
dp[1] = 1;
dp[2] = 6;
for (lli i = 3; i <= n; i++) {
lli x = 2 * i - 1;
lli combs = x * (x + 1) / 2;
dp[i] = (dp[i - 1] * combs) % mod;
}
return dp[n];
}
};
int main() {
Solution obj;
cout << obj.countOrders(2);
}
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