大数处理问题:
规律是:f(n)=f(n-1)*4+1;
#include <iostream>
#include <cstdio>
using namespace std;
int a[101];
int main()
{
int n, i, m, t, j, c;
cin>>n;
while (n--)
{
cin>>m;
if (m==1)
{
cout<<1<<endl;
continue;
}
a[0]=1;
t=0;
for (i = 1; i<m; i++)
{
c=0;
for (j = 0; j<=t; j++)
{
a[j]=a[j]*4+c;
c=a[j]/10000;
a[j]=a[j]%10000;
}
if (c!=0)
{
t++;
a[t]=c;
}
a[0]++;
}
cout<<a[t];
for (i = t-1; i>=0; i--)
printf("%04d", a[i]);
cout<<endl;
}
return 0;
}