//Karel finds the midpoint in the world. It is not the center.

function main() {

markWalls();
putBeepersDown();
turnAround();
move();
putBeeper();
turnAround();
goToWall();
turnAround();
lastBeeperStanding();

}

//Karel moves to end walls, marking them with beepers

function markWalls() {

goToWall();
putBeeper();
turnAround();
goToWall();
putBeeper();
turnAround();
move();

}

function goToWall() {
while(frontIsClear()) {
move();
}
}

 

//Karel starts putting beepers down to find the midpoint of the world.

function putBeepersDown() {
while(noBeepersPresent()) {
move();
if (beepersPresent()) {
turnAround();
move();
putBeeper();
move();
}
}
}

function lastBeeperStanding() {
while (frontIsClear()) {
if (beepersPresent()) {
pickBeeper();
}
move();
}
pickBeeper();
}