ll@n,@a[n],xl[n],yl[n],xr[n],yr[n],mi,ma,x,y,s,z=-ll_inf; mi=ma=0,x=-ll_inf,y=ll_inf,s=0; rep(i,n){ s+=a[i]; xl[i]=x>?=s-mi; yl[i]=y?=s; } mi=ma=0,x=-ll_inf,y=ll_inf,s=0; rrep(i,n){ s+=a[i]; xr[i]=x>?=s-mi; yr[i]=y?=s; } rep(i,n-1){ z>?=xl[i]*xr[i+1]; z>?=yl[i]*yr[i+1]; } wt(z);