[BZOJ2875]NOI2012随机数生成器|矩阵乘法

#include<cstdio>
#include<iostream>
#include<cmath>
#include<memory.h>
#define ll long long
using namespace std;
ll m,a,c,x0,n,g,an;
struct ju{
ll a[2][2];
int n,m;
}ans,t;
ll mul(ll a,ll b)
{
if (b>a) swap(a,b);
if (b==0) return 0ll;
ll c=mul(a,b/2);
c=(c+c)%m;
if (b%2==1) c=(c+a)%m;
return c;
}
ju operator*(ju a,ju b)
{
ju ans;
memset(ans.a,0,sizeof(ans.a));
ans.n=a.n;ans.m=b.m;
for (int i=0;i<a.n;i++)
for (int j=0;j<b.n;j++)
for (int k=0;k<b.m;k++)
ans.a[i][k]=(ans.a[i][k]+mul(a.a[i][j],b.a[j][k]))%m;
return ans;
}
ju pow(ju a,ll b)
{
if (b==1) return a;
ju c=pow(a,b/2);
c=c*c;
if (b%2==1) c=c*a;
return c;
}
int main()
{
scanf("%lld%lld%lld%lld%lld%lld",&m,&a,&c,&x0,&n,&g);
t.a[0][0]=1ll;t.a[0][1]=0ll;t.a[1][0]=1ll;t.a[1][1]=a;t.n=2;t.m=2;
ans.a[0][0]=c;ans.a[1][0]=x0;ans.n=2;ans.m=1;
ans=pow(t,n)*ans;
cout<<ans.a[1][0]%g;
}