An infinite recursive call is not an infinite loop
Merge pull request #4 from cocoatomo/master

An infinite recursive call is not an infinite loop
sicp chapter1 exercise1.9~1.10
Merge pull request #5 from ayato0211/master

sicp chapter1 exercise1.9~1.10
Merge branch 'master' of github.com:sicp-reading/sicp-answers