1. A program that counts the Flesch Score of a text. Code here. Don't know if the syllables are computed correctly.
2. A program that searches a wordlist for minimal pairs. Code here. Example here. The format of the wordlist is restrictive and the minimal pairs are printed twice!
3. A program that obfuscates the input, which means that first and last letter are the same but everything in between is mixed around. Code here.
4. A program that constructs a tree from a file and searches for the common minimal ancestor of two nodes. Code here. Example here.