12. Checking if two text blocks are isomorphic

Two text blocks are isomorphic if the resulting strings are isomorphic. Two string literals are considered isomorphic if we can map every character of the first string to every character of the second string in a one-to-one fashion.

For example, consider that the first string is “abbcdd" and the second string is “qwwerr". The one-to-one character mapping is shown in Figure 1.8:

Figure 1.8: One-to-one character mapping between two strings

So as you can see in Figure 1.8, character “a” of the first string can be replaced by character “q” of the second string. Moreover, character “b” of the first string can be replaced by character “w” of the second string, character “c” by character “e”, and character “d” by character “r”. Obviously, vice versa is also true. In other words, these two strings...