广义肥波 欧拉降幂

 

 

 

 

 

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
const int maxn=1e5+10;
const ll mod=1e9+7;
ll f[maxn];
ll quick(ll a,ll b)
{
    ll sum=1;
    while(b){
        if(b%2) sum=(sum*a)%mod;
        a=a*a%mod;
        b=b/2;
    }
    return sum;
}
int main()
{
    ll a,b,m,n;
    scanf("%lld%lld%lld%lld",&a,&b,&m,&n);
    f[1]=1;
    f[2]=1;
    for(int i=3;i<=n;i++){
        f[i]=(a*f[i-1]+b*f[i-2])%(mod-1);
    }
  //  printf("%d\n",f[n]);
    ll ans=quick(m,f[n]);
    printf("%lld\n",ans);
    return 0;
}