How to fix Python doesn't print all my string

I write some code, I want to print everything, but in one place the last character is not printed

a = input("Input Text\n")
b = []
i = 0
while i < len(a):
    b.append(a[0:i])
    i = i+1

for c in b:
    print(c)
temp = ''
for i in range(-1, -len(b), -1):
    temp = b[i]
    print(temp)

Example:

input text = 'abc', it will print this

a, ab, ab, a

I think you can rework your initial while loop to fit the second half of your prints

a = input("Input Text\n")
b = []

#Take slice from front to back
i = 0
while i < len(a):
    #Take slice from first index till the last
    b.append(a[:i+1])
    i = i+1

#Take slice from back to front
i = len(a)-1
while i > 0:
    # Take slice from last index till the first
    b.append(a[:i])
    i = i-1

for c in b:
    print(c)

The output will be

Input Text
helloworld
h
he
hel
hell
hello
hellow
hellowo
hellowor
helloworl
helloworld
helloworl
hellowor
hellowo
hellow
hello
hell
hel
he
h