35 multiple-choice questions in College Board exam style. Each has four choices and a full explanation of why each option is right or wrong.
Trace the code carefully: track each variable’s value step by step.
Watch integer division and precedence: int / int truncates, and * / % come before + −.
Remember String indices start at 0 and substring(from, to) excludes to.
Read the explanations even when you got it right, and use the Java Quick Reference for method signatures.