Μετατρέψτε την for σε ισοδύναμη while
for i in range(50,40,10):
print i
i=50
while i<40
i=i+10
while i>40:
while i<10:
i=i+40
for i in range(20,40,10):
i=20
while i<40:
i=10
while i<20:
for i in range(10):
i=0
i=i+1
while i>10:
while i<0:
for i in range(20,10,-5):
i=i+5
i=i-5
for i in range(10,5,-5):
while i<5:
while i>5:
for i in range(12,10,-1):
i=12
i=i-1