class program {

define half-turn() {
    turnleft();
    turnleft();
}

define turnright() {
    iterate(3) {
        turnleft();
    }
}

define go-forward() {
    if (frontIsClear) {
        move();
    } else {
        turnoff();
    }
}

define go-left() {
    if (leftIsClear) {
        turnleft();
        move();
        turnright();
    } else {
        turnoff();
    }
}

define go-back() {
    half-turn();
    if (frontIsClear) {
        move();
        half-turn();
    } else {
        half-turn();
        turnoff();
    }
}

define step-1() {
    go-forward();
    go-left();
    go-forward();
}

define step-2() {
    turnright();
    go-forward();
}

define step-3() {
    go-forward();
    go-back();
    go-back();
}

define dance() {
    pickbeeper();
    if (nextToABeeper) {
        pickbeeper();
        if (nextToABeeper) {
            pickbeeper();
            step-3();
        } else {
            step-2();
        }
    } else {
        step-1();
    }
}

program() {
    while (nextToABeeper) {
        dance();
    }
    turnoff();
}

}