卡特兰数
#include<cstdio> #include<cstring> #include<algorithm> using namespace std; int f[1001]; int main() { freopen("stack.in","r",stdin); freopen("stack.out","w",stdout); int n; scanf("%d",&n); f[0]=1; f[1]=1; for(int i=2;i<=n;i++) for(int j=1;j<=i;j++) f[i]=(f[i]+f[j-1]*f[i-j])%7; printf("%d",f[n]); }