Some errors

1.Notebook 07, Question 21:
if s[0] == "UP":  
        x -= int(s[1])  -> y+=
    if s[0] == "DOWN":
        x += int(s[1]) -> y-=
    if s[0] == "LEFT":
        y -= int(s[1]) -> x-=
    if s[0] == "RIGHT":
        y += int(s[1]) ->  x+=

2.Noteboook 17, Question 67, at first solution:
print("Middle value:", x) -> print("Middle index:", x)