long N=1024,d[1<<16]={1},A[1024],r;k,m,x,y,a,i,j,l;main(n){scanf("%d%d%d%d",&n,&m,&x,&y);for(;m--;)scanf("%d",&a),k+=(A[a]?0:++A[a]);for(;i0));}for(;x