hdu3565 Bi-peak Number (有上界和下界的数位dp)
Problem Description A peak number is defined as continuous digits {D0,D1 … Dn-1} (D0 0 and n = 3),which exist Dm (0 m n – 1) satisfied Di-1 Di (0 i = m) and Di Di+1 (m = i n – 1). A number is called bi-peak if it is a concatenation of t