<reponame>sdlab-naist/Teddy-plus
def i47():
    (seat_A1, seat_A2) = (seat_A2, seat_A1)

def i48(var_A, var_B):
    (var_A, var_B) = (var_B, var_A)

def i49():
    (english, math) = (math, english)

def i50(arr):
    (arr[j], arr[j+1]) = (arr[j+1], arr[j])

