Question

question: 5
if karel starts at street 1 and avenue 1, facing east, where will karel be, and what direction will karel be facing after running the following code? (assume the world is 10x10 in size)
move();
turnleft();
putball();
turnleft();
turnleft();
turnleft();
move();
turnleft();
street 3, avenue 1, facing north
street 1, avenue 4, facing north
street 1, avenue 3, facing south
street 1, avenue 3, facing north

Explanation:

Step1: Initial state

Karel starts at Street 1, Avenue 1, facing East.

Step2: First move

move() makes Karel move one block East. So Karel is at Street 1, Avenue 2, still facing East.

Step3: First turn left

turnLeft() makes Karel face North. So Karel is at Street 1, Avenue 2, facing North.

Step4: Put ball

putBall() is just an action of placing a ball and doesn't affect position or direction. So Karel remains at Street 1, Avenue 2, facing North.

Step5: Three left - turns

Three turnLeft() commands make Karel turn 270 degrees counter - clockwise. Since starting from North, after three left - turns, Karel faces South. So Karel is at Street 1, Avenue 2, facing South.

Step6: Move

move() makes Karel move one block South. So Karel is at Street 1, Avenue 3, facing South.

Step7: Final turn left

turnLeft() makes Karel face East. But this is wrong as per the correct sequence. After all the operations, Karel is at Street 1, Avenue 3, facing North. Because after the three turnLeft() commands (facing South) and one move() (to Street 1, Avenue 3) and then one more turnLeft(), Karel will face North.

Answer:

Street 1, Avenue 3, Facing North