A three-digit code for certain logs uses the digits 0,1,2,3,4,5,6,7,8,9 according to the following constraints. The first digit cannot be 0 or 1, the second digit must be 0 or 1,and the second and the third digits cannot both be 0 in the same code. How many different codes are possible?
京公网安备11010202008513号 京ICP证101109号 京ICP备12012021号
发表于 2008-6-3 22:54:00
楼主
