function assert(x) { if (!x) throw 1; }

try {
    var a = [1, 2, 3];

    assert(typeof a === "object");
    assert(a.length === 3);
    assert(a[0] === 1);
    assert(a[1] === 2);
    assert(a[2] === 3);

    a[1] = 5;
    assert(a[1] === 5);
    assert(a.length === 3);

    a.push(7);
    assert(a[3] === 7);
    assert(a.length === 4);

    console.log("PASS");
} catch (e) {
    console.log("FAIL: " + e);
}