82 lines
1.8 KiB
C++
82 lines
1.8 KiB
C++
#include<cstdio>
|
|
#include<ctype.h>
|
|
#include<algorithm>
|
|
#include<iostream>
|
|
#include<cstring>
|
|
#include<vector>
|
|
#include<cstdlib>
|
|
#include<stack>
|
|
#include<cmath>
|
|
#include<queue>
|
|
#include<set>
|
|
#include<map>
|
|
#include<ctime>
|
|
#include<string.h>
|
|
#include<string>
|
|
#include<sstream>
|
|
#include<bitset>
|
|
using namespace std;
|
|
#define ll __int64
|
|
#define ull unsigned long long
|
|
#define eps 1e-8
|
|
#define NMAX 1000000005
|
|
#define MOD 1000000007
|
|
#define lson l,mid,rt<<1
|
|
#define rson mid+1,r,rt<<1|1
|
|
#define PI acos(-1)
|
|
template<class T>
|
|
inline void scan_d(T &ret)
|
|
{
|
|
char c;
|
|
int flag = 0;
|
|
ret=0;
|
|
while(((c=getchar())<'0'||c>'9')&&c!='-');
|
|
if(c == '-')
|
|
{
|
|
flag = 1;
|
|
c = getchar();
|
|
}
|
|
while(c>='0'&&c<='9') ret=ret*10+(c-'0'),c=getchar();
|
|
if(flag) ret = -ret;
|
|
}
|
|
ll dp[100005],sum[100005];
|
|
void cal()
|
|
{
|
|
ll a = 3,b = MOD-2,ret = 1;
|
|
while(b)
|
|
{
|
|
if(b&1) ret = ret*a%MOD;
|
|
a = a*a%MOD;
|
|
b >>= 1;
|
|
}
|
|
cout<<ret<<endl;
|
|
}
|
|
int main()
|
|
{
|
|
dp[1] = dp[2] = 1;
|
|
sum[0] = 1;
|
|
sum[1] = 2;
|
|
ll tmp = 1;
|
|
for(int i = 3; i <= 100000; i++)
|
|
{
|
|
if(i%2)
|
|
{
|
|
ll a = ((tmp*(tmp-1LL+MOD)%MOD*(tmp-2LL+MOD)%MOD)*166666668LL%MOD + tmp*(tmp-1LL+MOD)%MOD + tmp)%MOD;
|
|
dp[i] = (sum[i/2-1]*((tmp*(tmp-1LL+MOD)%MOD)*500000004LL%MOD+tmp)%MOD+a)%MOD;
|
|
}
|
|
else
|
|
{
|
|
ll a = tmp*sum[i/2-2]%MOD;
|
|
tmp = (tmp*(tmp-1LL+MOD)%MOD*500000004LL%MOD+tmp+a)%MOD;
|
|
dp[i] = (tmp*(tmp-1LL+MOD)%MOD*500000004LL%MOD+tmp)%MOD;
|
|
sum[i/2] = (sum[i/2-1]+tmp)%MOD;
|
|
}
|
|
}
|
|
int n;
|
|
while(~scanf("%d",&n) && n)
|
|
{
|
|
printf("%I64d\n",dp[n]);
|
|
}
|
|
return 0;
|
|
}
|