如何创建一个使用python中的嵌套while循环进行求幂的程序？

Question

x=eval(input('Enter a number greater than 1: '))
e=eval(input('Enter an exponenet greater than 1: '))
i=2
j=1
power=1
while i <= x:
  while j <=e:
    power=power*i
    j=j+1
  print(i, 'to the power',e, '=', power)
  i=i+1

This is my code so far: the output of this code is when 5 and 3 are entered is

2 to the power 3 = 8

3 to the power 3 = 8

4 to the power 3 = 8

5 to the power 3 = 8

I need the output to be:

2 to the power 3 = 8

3 to the power 3 = 27

4 to the power 3 = 64

5 to the power 3 = 125

I need to use nested while loops, and the exponentiation operator (**) cannot be used. I would appreciate any help and thank you in advance!

Answer 1

You need to reset power and j before entering in the nested loop.

x=eval(input('Enter a number greater than 1: '))
e=eval(input('Enter an exponenet greater than 1: '))
i=2

while i <= x:
        j = 1
        power = 1
        while j <=e:
           power=power*i
           j=j+1
        print(i, 'to the power',e, '=', power)
        i=i+1

Answer 2

This can be done with addition only, for x**power :

value = x                  #ex 3**3
temp = x
result = x
while power > 1:             
    while value > 1: 
        temp += result      #1st loop: 3 + 3 + 3 = 9       
        value -= 1          #2nd loop  9 + 9 + 9 = 27
    result = temp           
    value = x
    power -= 1
print(f"{x} to the power of {power} is {result}")

Note however that if power = 0 this fails, as it does with power = -1 .

Answer 3

The more “low tech” way to do this defines successively the functions successor, addition, multiplication and exponentiation.

def succ(x):
    return x

def add(x, y):
    result = x
    while y > 0:
        result = succ(x)
        y -= 1
    return result

def mult(x, y):
    result = x
    while y > 1:
        result = add(result, x)
        y -= 1
    return result

def exp(x, y):
    result = 1
    while y > 0:
        result = mult(result, x)
        y -= 1
    return result

All four are canonical examples of primitive recursive functions on unary numbers. They are best implemented using recursion or for loops.

See Knuth's up-arrow notation for the next (hyper)operations.

Answer 4

Here you go!

The only problem with your code was that the variables were not re-initialized to 1. I fixed it for you!

x=eval(input('Enter a number greater than 1: '))
e=eval(input('Enter an exponenet greater than 1: '))
i=2
j=1
power=1
while i <= x:
    while j <=e:
        power = power * i
        j=j+1
    print(i, 'to the power',e, '=', power)
    power = 1
    j = 1 
    i = i + 1