#include <bits/stdc++.h> using namespace std; typedef signed long long ll; #define _P(...) (void)printf(__VA_ARGS__) #define FOR(x,to) for(x=0;x<(to);x++) #define FORR(x,arr) for(auto& x:arr) #define FORR2(x,y,arr) for(auto& [x,y]:arr) #define ALL(a) (a.begin()),(a.end()) #define ZERO(a) memset(a,0,sizeof(a)) #define MINUS(a) memset(a,0xff,sizeof(a)) template<class T> bool chmax(T &a, const T &b) { if(a<b){a=b;return 1;}return 0;} template<class T> bool chmin(T &a, const T &b) { if(a>b){a=b;return 1;}return 0;} //------------------------------------------------------- int H,W; ll K,mo; ll modpow(ll a, ll n = mo-2) { ll r=1;a%=mo; while(n) r=r*((n%2)?a:1)%mo,a=a*a%mo,n>>=1; return r; } ll p2[30]; ll sc[30]; ll ret; void dfs(int mask_filled,int mask_cand) { int nf=0; int y,x,i; int d[]={0,1,0,-1}; FOR(y,H) FOR(x,W) { //もう埋まってる if(mask_filled&(1<<(y*W+x))) { nf++; continue; } int ok=0; FOR(i,4) { int ty=y+d[i]; int tx=x+d[i^1]; if(ty<0||ty>=H||tx<0||tx>=W) continue; //隣が埋まっているならok if(mask_filled&(1<<(ty*W+tx))) { nf++; ok=1; break; } } //埋めることは不可 if(mask_cand&(1<<(y*W+x))) continue; if(ok) { mask_cand |= (1<<(y*W+x)); dfs(mask_filled | (1<<(y*W+x)), mask_cand); } } ret+=p2[H*W-nf]*sc[__builtin_popcount(mask_filled)]%mo; } void solve() { int i,j,k,l,r,x,y; string s; cin>>H>>W>>K>>mo; p2[0]=1; FOR(i,25) p2[i+1]=p2[i]*2%mo; FOR(i,26) sc[i]=modpow(i,K); ll weight=0; for(i=1;i<=H*W;i++) (weight+=modpow(i))%=mo; (weight*=modpow(1<<(H*W)))%=mo; FOR(i,H*W) dfs(1<<i,(1<<(i+1))-1); ret=ret%mo*weight%mo; cout<<ret%mo<<endl; } int main(int argc,char** argv){ string s;int i; if(argc==1) ios::sync_with_stdio(false), cin.tie(0); FOR(i,argc-1) s+=argv[i+1],s+='\n'; FOR(i,s.size()) ungetc(s[s.size()-1-i],stdin); cout.tie(0); solve(); return 0; }