Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others)
Total Submission(s): 38217 Accepted Submission(s):
15342
#include<stdio.h>
#include<math.h>
#include<stdlib.h>
#define LL long long
LL f[55];
void biao()
{
f[1]=3;
f[2]=f[3]=6;
int i,j;
for(i=4;i<55;i++)
{
f[i]=f[i-1]+2*f[i-2];
}
}
int main()
{
int n,m,j,i;
LL sum;
biao();
while(scanf("%d",&n)!=EOF)
{
printf("%lld\n",f[n]);
}
return 0;
}
hdoj 2045 不容易系列之(3)—— LELE的RPG难题
原文：http://www.cnblogs.com/tonghao/p/4975785.html