Consider all strictly decreasing functions from {1,2,3,4} to {1,2,3,4,5,6}, or in other words, all functions defined on {1,2,3,4} such that f(1)>f(2)>f(3)>f(4). Draw a decision tree so that the leaves are in lexicographical order when read from left to right. Then answer the following questions:
(a) What is the rank of 5431?
(b) What function has rank 0?
I have been looking all over the internet but I could not find a good resource for decision tree. I would be very appreciate it if anyone could show me how to approach this problem. Thanks