数论-「noi2012」随机数生成器

#include <cmath>
#include <cstring>
#include <cstdlib>
#include <iostream>
#include <algorithm>
#include <queue>
#include <stack>
#define ll long long
using namespace std;
ll m,a,c,x0,n,g;
ll (ll x,ll y)
{
    ll ans=0;
    while(y)
    {
        if(y%2) ans=(ans+x)%m;
        x=(x+x)%m;
        y/=2;
    }
    return ans%m;
}
ll qpow(ll x,ll y)
{
    ll ans=1;
    while(y)
    {
        if(y%2==1) ans=qpow_add(ans,x);
        x=(ll)qpow_add(x,x)%m;
        y/=2;
    }
    return ans%m;
}
ll qmul(ll x,ll y)
{
    if(y==1) return (x+1)%m;
    if(y==0) return 1;
    if(y%2) return qpow_add((qpow(x,y/2+1)%m+1)%m,qmul(x,y/2)%m)%m;
    return qpow(x,y)%m+qpow_add((qpow(x,y/2)+1)%m,qmul(x,y/2-1)%m)%m;
}
int main()
{
    scanf("%lld%lld%lld%lld%lld%lld",&m,&a,&c,&x0,&n,&g);
    x0%=m;
    ll a0=qpow(a,n)%m;
    ll temp1=qpow_add(a0,x0)%m;
    ll temp2=qpow_add(qmul(a,n-1)%m,c%m)%m;
    ll ret=(temp1+temp2)%m%g;
    printf("%lldn",ret);
    return 0;
}