ll@n,@x,@y,d[y+1][x+1]{},z=0;
rep(n){
	ll@a,@b,@c;
	rrep(v,b,y+1){
		rrep(u,a,x+1){
			z>?=d[v][u]>?=c+d[v-b][u-a];
		}
	}
}
wt(z);