Files
OI-source/2.580.cpp
2023-08-03 09:22:52 +08:00

18 lines
295 B
C++

#include<cstdio>
int f[40],g[40],n;
int main()
{
#ifdef local
freopen("pro.in","r",stdin);
#endif
g[0]=1;g[1]=2;g[2]=4;
for(n=3;n<=30;n++)
{
f[n]=1<<(n-3);
for(int i=2;i<=n-2;i++) f[n]+=g[i-2]<<n-i-2;
g[n]=(1<<n)-f[n];
}
while(scanf("%d",&n)==1&&n) printf("%d\n",f[n]);
return 0;
}