print('------------------') # table heading
C = -20                    # start value for C
dC = 5                     # increment of C in loop
while C <= 40:             # loop heading with condition
    F = (9.0 / 5) * C + 32     # 1st statement inside loop
    print(C, F)             # 2nd statement inside loop
    C = C + dC             # last statement inside loop
print('------------------') # end of table line

"""
Terminal> python c2f_table_while.py 
------------------
-20 -4.0
-15 5.0
-10 14.0
-5 23.0
0 32.0
5 41.0
10 50.0
15 59.0
20 68.0
25 77.0
30 86.0
35 95.0
40 104.0
------------------
"""