Python 3.X: Call Outside Variable In Nested For Loop

Question

I've nested one for loop inside of another. The first loop simply iterates over the second loop five times; the second loop iterates over the same simple block of code five times.

In total, these loops should perform the same job twenty-five times.

x = 0

for y in range(0, 5,):
    for z in range(0, 5,):
        print(str(int(x + 1)) + ". Hello")

I expected the output to be:

1. Hello.
2. Hello.
3. Hello.
4. Hello.
5. Hello.

Twenty-five times, with each proceeding line increasing the number's value by one.

Instead, the output was:

1. Hello

This output repeated itself twenty-five times. How do I fix this problem and receive the output I want?

To be clear, you do add 1 to x in int(x + 1) but you don't store the result in x. Like some of the answers are suggesting, by separating the computation and storage x = x + 1 or x += 1 from printing the result print(str(x) + ". Hello"), you solve the problem. Some languages would allow you to do the whole thing in one go, but using the assignment in Python looks just like assigning a value to a named parameter, so print(x = x + 1) confuses Python and isn't very clear to begin with. — Grismar
– Grismar, Commented Jan 31, 2019 at 0:54

Nick Perkins · Accepted Answer · 2019-01-31 00:56:20Z

1

You aren't updating the value for x as you loop through.

Try this:

x = 0

for y in range(0, 5,):
    for z in range(0, 5,):
        x+=1
        print(str(x) + ". Hello")

edited Jan 31, 2019 at 0:56

answered Jan 31, 2019 at 0:50

Nick Perkins

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Osman Mamun · Accepted Answer · 2019-01-31 00:50:28Z

0

You are almost there. Just add one extra line

x = 0

for y in range(0, 5,):
    for z in range(0, 5,):
        print(str(int(x + 1)) + ". Hello")
        x += 1

answered Jan 31, 2019 at 0:50

Osman Mamun

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1 Comment

Watch_Doggos Over a year ago

Oh, thank you, I didn't realize I had to separately modify the variable's value when using it in a loop.

Asm Programmer · Accepted Answer · 2019-01-31 01:02:03Z

0

you can also use this :

   i = 0
for y in range(0, 5):
    for z in range(0, 5):
        i = i+1
        print(str(i) + "." " Hello.")

answered Jan 31, 2019 at 1:02

Asm Programmer

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