According to the meaning of the question, we need to solve a linear inequality of 12 yuan, which can be solved by linear programming. Rewrite this inequality into the standard form:

-D3 * e 1-D2 * E2-d 1 * E3-C3 * E4-C2 * E5-c 1 * E6-B3 * E7-B2 * E8-b 1 * e9-a3 * e 10-a2 * e 1 1

-a 1 * e 12+e 1+E2+E3+E4+E5+E6+E7+E8+e9+e 10+e 1 1+e 12 & lt； = 0

Then use integer programming to solve this problem, and get:

e 1= 1，e2= 1，e3= 1，e4= 1，e5= 1，e6= 1，e7= 1，e8= 1，e9= 1，e 10=4，e 1 1 = 0

Therefore, when E 1 = 1, E2 = 1, E3 = 1, E4 = 1, E5 = 1, E6 = 1, E7 =/. When e 12=2, the formula holds, while e 1, e2, E3...E 12 are positive integers respectively.