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tranform a for into a while but keep the same properties? [duplicate]

This question already has answers here:
Converting for loops to while loops in python
(3 answers)
Closed 2 years ago.
def p(l):
x = True
y = len(l)
for z in range(y):
if (sum(l[z+1:]) == sum(l[:z])):
x = False
return z
if x:
return -1
So I would like to transform the for in my code into a while but keep all the same properties is there any way to do it without disturbing the code it self?

If you just want to convert a for loop to a while loop, these two loops are equivalent:
for x in range(y):
# do stuff
x = 0
while x < y:
# do stuff
x += 1

You'll need to instantiate the z variable to 0 and then you can use a while loop to break once all elements of l have been checked.
Though in your case, I guess that it'll throw an indexError when it tries to do l[z+1], so you'll need y - 1 as the termination condition.
z = 0
while z < y:
if (sum(l[z+1:]) == sum(l[:z])):
x = False
return z
z += 1

Your code doesn't have any indents, but it seems, it should be like this.
range(y) means from 0 to y-1, so we start from 0: z = 0, and increase z by 1 every iteration: z += 1. The last value is y-1, so it must stop when z = y, so while conditions is z < y
x = True
y = len(l)
# for z in range(y):
z = 0
while z < y:
if (sum(l[z+1:]) == sum(l[:z])):
x = False
return z
z += 1 # increase z value
if x:
return -1

Return to the top after results

I'm currently experimenting on different ways to solve exponents(via addition). As soon as the results are printed, I could not use the program anymore.
I've tried continue and break, but they're not appropriate
x = int(input())
y = 0
z = x
while z != 0:
y += x
z -= 1
if z <= 0:
y *= x
print(y)
I just need to re-use the application again after the previous results, and keep using it until it is closed.

You will need to wrap everything in a while loop and give some type of exit condition.
x = input()
while x != 'exit':
x = int(x)
y = 0
z = x
while z != 0:
y += x
z -= 1
if z <= 0:
y *= x
print(y)
x = int(input())
print('You chose to end the program, goodbye!')

While-loop with an or-condition

I want it to stop once one of the variables gets to the desired number. Why does this code wait until both variables equal 20 or greater to end?
z = 20
x = 1
y = 0
while x < z or y < z:
inp = int(input('enter a number'))
if x > y:
y += inp
elif y > x:
x += inp
print(x, y)
or using something like these examples just keeps adding and never stops:
while x != z or y != z:
while x or y < z:
while x or y != z:

If the loop must stop when at least one of the variables is >= z, then you must use and to connect the conditions:
while x < z and y < z:
In your code, by using or you state that as long as one of the variables is < z, the loop must continue - and that's not what you want.

Sum of numbers from 1 to 5 in loop

To simplify my scenario, I am redefining my question here.
I want to add numbers from 1 to 5 in loop. X should be 1,2,3,4,5. and start with Y as 0. Y = X + Y should give the sum of 1 through 5.
Requirement: I want to start y as 0 and want y to hold latest add_sum value.
Expected output:
1st iteration: y = 1 (x = 1, y = 0)
2st iteration: y = 3 (x = 2, y = 1)
3st iteration: y = 6 (x = 3, y = 3)
...
...
so on
I am new to python coding, Can anyone help me for this?

Use reduce
reduce(lambda x, y: x + y, range(6))

As mentioned in the comments, fixing your syntax and running your code seems to work just fine.
def read_num():
for num in range (1,5):
x = num
add_sum(x)
def add_sum(x):
global y
y = x + y
print ("y =", y)
y = 0
read_num()
If you want x to be 1 thru 5 inclusive, you have to use range(1,6) instead

y = 0 # Assign value 0 to variable 'y'
for x in xrange(1, 6): # Cycle from 1 to 5 and assign it to variable x using iterator as we need just 1 value at a time
print '(x=%s, y=%s)' % (x, y) # Display value of 'x' & 'y' variables to user for debug & learning purpose
y += x # Adding x to the y.
print 'y=%s' % y # Display result of sum accumulated in variable 'y'
Edit: added comments to the code as requested in comments.

Generating Perfect Squares python

I am trying to write the simplest code possible that will continuously print out Perfect Squares. My code so far reads this
x = 1
y = 1
while True:
final = x * y
print final
x = x + 1
y = y + 1
When I run it, I get a syntax error. The red bit is on the "final" in "print final"
Apologies if it is a really basic error, but I'm stumped.
Thanks for taking the time to read this

I assume you're using Python 3. print is now a function in Python 3.
Do print(final) instead of print final.
Also, it seems like your x and y values are holding the same thing. Why not discard one of them and use just one?
x = 1
while True:
final = x * x
print(final)
x = x + 1
Or better yet, use the builtin exponentiation operator **.
x = 1
while True:
final = x **2
print(final)
x += 1
Also, your code seems to be going into an infinite loop. You may need a condition to break it.
For example, if you want to break when x reaches 10, just add a condition in the while loop, like follows:
x = 1
while True:
final = x **2
print(final)
x += 1
if x == 10:
break
OR Specify a condition in the whilestatement, like follows:
x = 1
while x < 10:
final = x **2
print(final)
x += 1
OR Use a for loop.
for i in range(10):
print(i**2)

In Python 3, print is no longer a statement but a function, so you must enclose what you want to print in parentheses:
print(final)
Here's a link about the function.
You also have an IndentationError, y = y + 1 should be given a space.
And you can simplify that to y += 1 (which is the same thing, in regards to integers)
You can also add a condition to the while-loop:
x = 0
while x < 5:
print x ** 2
x += 1
Prints:
0
1
4
9
16

I would reccomend using Python 3 if you're not already. Also, as x and y are the same value at all times you only need one of them. So instead of reading:
x = 1
y = 1
while True:
final = x * y
print final
x = x + 1
y = y + 1
You should write:
x = 1
while True:
final = x * x
print(final)
x = x + 1
Hope this helped!
Jake.