P3414 SAC#1 - 组合数

3

4

 1 #include<iostream>
 2 #include<cstdio>
 3 #include<cstring>
 4 #include<cmath>
 5 #define ll long long 
 6 using namespace std;
 7 const int mod=6662333;
 8 ll fastpow(ll m,ll p)
 9 {
10     ll ans=1;
11     ll base=m%mod;
12     while(p!=0)
13     {
14         if(p%2==1)
15         ans=(ans*base)%mod;
16         
17         base=(base*base)%mod;
18         p=p/2;
19     }
20     return ans;
21 }
22 int main()
23 {
24     ll n;
25     cin>>n;
26     cout<<(fastpow(2,n-1)%mod);
27     return 0;
28 }