Precedence and compound assignment

Compound assignment: x += 5 means x = x + 5. Same for -=, *=, /= and %=. One subtlety: x += 2.5 compiles even when x is an int (the compound form contains a hidden cast) — but plain x = x + 2.5 does not. Prefer the explicit cast for clarity; know the rule for tracing.

Operator precedence ladder (high to low):

1. ++ -- ! (unary)
2. * / %
3. + -
4. relational < > <= >=
5. equality == !=
6. &&
7. ||
8. assignment = += -= ...

Two classics:

System.out.println(3 < 5 == true);    // true — relational before equality
boolean ok = 5 > 3 && 2 > 1 || 1 > 2; // (true && true) || false → true

When in doubt (in reading or writing), use parentheses. The exam expects you to evaluate by the ladder, but human readers thank you for clarity.