ll@N,@A[N],D[N][2]{{-1d15,-*A}};rep[D,i](d,1,N)*d=max(0[d-2],1[d-2]+A[i]),d[1]=max(1[d-2],0[d-2]-A[i]);wt(D[N-1][0]>?=D[N-1][1]);