public class UnusedCompoundAssignment {
    void this_is_unused() {
        int x = 0; // violation expected (line 3)
        x += 2;    // doesn't count as usage
    }
    void transitive_used_but_unused1() {
        int a = 1; // _no_ violation expected, a is used
        int b = a; // _no_ violation expected, b is used
        int c = b; // violation expected (line 9)
    }
    void transitive_used_but_unused2() {
        int a, b, c; // 1 violation expected, only c is unused (line 12)
        a = 1;
        b = a;
        c = b;
    }
    void transitive_used() {
        int a, b, c; // _no_ violation expected
        a = 1;
        b = a;
        c = b;
        System.out.println(c); // usage
    }
    void this_is_used() {
        int y = 0; // _no_ violation expected
        y += 2;
        System.out.println(y); // usage
    }
}