CF708E Student's Camp

#include<bits/stdc++.h>
#define Tp template<typename Ty>
#define Ts template<typename Ty,typename... Ar>
#define W while
#define I inline
#define RI register int
#define LL long long
#define Cn const
#define CI Cn int&
#define gc getchar
#define D isdigit(c=gc())
#define pc(c) putchar((c))
#define min(x,y) ((x)<(y)?(x):(y))
#define max(x,y) ((x)>(y)?(x):(y))
using namespace std;
namespace Debug{
    Tp I void _debug(Cn char* f,Ty t){cerr<<f<<'='<<t<<endl;}
    Ts I void _debug(Cn char* f,Ty x,Ar... y){W(*f!=',') cerr<<*f++;cerr<<'='<<x<<",";_debug(f+1,y...);}
    Tp ostream& operator<<(ostream& os,Cn vector<Ty>& V){os<<"[";for(Cn auto& vv:V) os<<vv<<",";os<<"]";return os;}
    #define gdb(...) _debug(#__VA_ARGS__,__VA_ARGS__)
}using namespace Debug;
namespace FastIO{
    Tp I void read(Ty& x){char c;int f=1;x=0;W(!D) f=c^'-'?1:-1;W(x=(x<<3)+(x<<1)+(c&15),D);x*=f;}
    Ts I void read(Ty& x,Ar&... y){read(x),read(y...);}
    Tp I void write(Ty x){x<0&&(pc('-'),x=-x,0),x<10?(pc(x+'0'),0):(write(x/10),pc(x%10+'0'),0);}
    Tp I void writeln(Cn Ty& x){write(x),pc('\n');}
}using namespace FastIO;
Cn int N=1.5e3+10,X=1e9+7,K=1e5+10;
int n,m,p,k,P[N],fac[K],ifac[K],G[N],Sr[N][N],Fr[N][N],H[N];
I int QP(RI a,RI b){RI s=1;W(b) b&1&&(s=1LL*s*a%X),a=1LL*a*a%X,b>>=1;return s;}
I int C(CI n,CI m){return 1LL*fac[n]*ifac[m]%X*ifac[n-m]%X;}
int main(){
    RI i,j,x,y;for(read(n,m,x,y,k),p=1LL*x*QP(y,X-2)%X,fac[0]=i=1;i<=k;i++) fac[i]=1LL*fac[i-1]*i%X;
    for(ifac[k]=QP(fac[k],X-2),i=k-1;~i;i--) ifac[i]=1LL*ifac[i+1]*(i+1)%X;
    for(i=0;i<=min(m,k);i++) P[i]=1LL*C(k,i)*QP(p,i)%X*QP(1-p,k-i)%X;
    for(i=1;i<=m;i++) G[i]=(G[i-1]+P[i-1])%X;
    for(Fr[0][m]=Sr[0][m]=1,i=1;i<=n;i++){
        for(j=1;j<=m;j++) H[j]=(H[j-1]+1LL*P[j-1]*Sr[i-1][j-1]%X)%X;
        for(j=1;j<=m;j++) Fr[i][j]=(1LL*P[m-j]*(Sr[i-1][m]-Sr[i-1][m-j])%X*G[j]%X-1LL*P[m-j]*H[j]%X)%X;
        for(j=1;j<=m;j++) Sr[i][j]=(Sr[i][j-1]+Fr[i][j])%X;
    }return writeln((Sr[n][m]+X)%X),0;
}