void main() {
    int[] a = new int[1];

    a[0] = 5;
    a[0] += 5;
    a[0] += 10;
    a[0] += 20;
    test(a[0]);

    a[0] = 5;
    a[0] -= 5;
    a[0] -= -10;
    a[0] -= 20;
    test(a[0]);

    a[0] = 5;
    a[0] *= 2;
    a[0] *= 3;
    a[0] *= 4;
    test(a[0]);

    a[0] = 100;
    a[0] /= 2;
    a[0] /= 3;
    a[0] /= 4;
    test(a[0]);

    a[0] = 100;
    a[0] %= 120;
    a[0] %= 90;
    a[0] %= 3;
    test(a[0]);
}