#include <iostream> #include <vector> #include <algorithm> typedef long long ll; using namespace std; const ll MOD=1e9+7; ll powmod(ll a, ll k, ll mod){ if(a==0) return 0; ll ap=a, ans=1; while(k){ if(k&1){ ans*=ap; ans%=mod; } ap=ap*ap; ap%=mod; k>>=1; } return ans; } ll inv(ll a, ll mod){ return powmod(a, mod-2, mod); } ll gcd(ll a, ll b){ if(b==0) return a; return gcd(b, a%b); } ll a[505], q[100010], dp[2][100010]; int qi[100010]; int main() { int n, k; ll b, p; cin>>p>>n>>k>>b; k=gcd(k, p-1); for(int i=0; i<n; i++) cin>>a[i]; ll r; for(r=1; r<p; r++){ bool dame=0; ll pp=1; for(int i=0; i<p-2; i++){ (pp*=r)%=p; if(pp==1){ dame=1; break; } } if(!dame) break; } q[0]=1; for(int i=1; i<p-1; i++) q[i]=q[i-1]*r%p; for(int i=0; i<p-1; i++) qi[q[i]]=i; dp[0][k]=1; for(int i=0; i<n; i++){ for(int j=0; j<=k; j++) dp[(i&1)^1][j]=dp[i&1][j]; for(int j=0; j<k; j++){ for(int l=0; l<(p-1)/k; l++){ ll m=(q[l*k]*a[i]+q[j])%p; if(m==0) (dp[(i&1)^1][k]+=dp[i&1][j]*k)%=MOD; else (dp[(i&1)^1][qi[m]%k]+=dp[i&1][j]*k)%=MOD; } } if(a[i]==0) (dp[(i&1)^1][k]+=dp[i&1][k]*(p-1))%=MOD; else (dp[(i&1)^1][qi[a[i]]%k]+=dp[i&1][k]*(p-1))%=MOD; } if(b==0) cout<<dp[n&1][k]<<endl; else cout<<dp[n&1][qi[b]%k]*inv((p-1)/k, MOD)%MOD<<endl; return 0; }