#include<bits/stdc++.h>

#define ll long long

using namespace std;

ll N,M,K,P,ans,ans2;

ll qpow(ll a,ll x){

    ll res=;while(x){

        if(x&) res=(ll)res*a%P;

        a=(ll)a*a%P; x>>=;

    }return res;

}

int main()

{

    scanf("%lld%lld%lld%lld",&N,&K,&M,&P); N%=P;

    ans=(ll)N*qpow(M,K-)%P;

    ll a=M,b=M+;

    if(a&) b/=; else a/=;

    ans2=(ll)a*b%P;

    ans2=(ll)ans2*qpow(M,K-)%P*(K-)%P;

    ans=(((ans-ans2)%P)+P)%P;

    printf("%lld\n",ans);

    return ;

}