I am a beginner in python programming. I wrote the following program but it doesn't execute as I want it to. Here is the code:
b=0
x=0
while b<=10:
print 'here is the outer loop\n',b,
while x<=15:
k=p[x]
print'here is the inner loop\n',x,
x=x+1
b=b+1
can somebody help me?? I will be grateful indeed! Regards, Gillani
Not sure what your problem is, maybe you want to put that x=0 right before the inner loop ?
Your whole code doesn't look remotely like Python code ... loops like that are better done like this:
for b in range(0,11):
print 'here is the outer loop',b
for x in range(0, 16):
#k=p[x]
print 'here is the inner loop',x
xrange(11). range creates a whole list and returns it to the caller. xrange returns a generator function, which delays allocation of elements until they are requested. For a 16 element array, it likely isn't a huge difference. However, if you are counting to 10,000, then xrange is definitely better.Because you defined the x outside of the outer while loop its scope is also outside of the outer loop and it does not get reset after each outer loop.
To fix this move the defixition of x inside the outer loop:
b = 0
while b <= 10:
x = 0
print b
while x <= 15:
print x
x += 1
b += 1
a simpler way with simple bounds such as this is to use for loops:
for b in range(11):
print b
for x in range(16):
print x
You need to reset your x variable after processing the inner loop. Otherwise your outerloop will run through without firing the inner loop.
b=0
x=0
while b<=10:
print 'here is the outer loop\n',b,
while x<=15:
k=p[x] #<--not sure what "p" is here
print'here is the inner loop\n',x,
x=x+1
x=0
b=b+1
When running your code, I'm getting the error:
'p' is not defined
which means that you are trying to use list p before anything is in it.
Removing that that line lets the code run with output of:
here is the outer loop 0 here is the inner loop 0 here is the inner loop 1 here is the inner loop 2 here is the inner loop 3 here is the inner loop 4 here is the inner loop 5 here is the inner loop 6 here is the inner loop 7 here is the inner loop 8 here is the inner loop 9 here is the inner loop 10 here is the inner loop 11 here is the inner loop 12 here is the inner loop 13 here is the inner loop 14 here is the inner loop 15 here is the outer loop 1 here is the outer loop 2 here is the outer loop 3 here is the outer loop 4 here is the outer loop 5 here is the outer loop 6 here is the outer loop 7 here is the outer loop 8 here is the outer loop 9 here is the outer loop 10 >>>
If you were intending to test the number of iterations of each loop in a nested while loop and compare it with that of a for loop, I have just the program for that! Here you go:
#Nested while loop
i=5
j=5
count=0
count1=0
while i>0:
count+=1
print("\t\t",count,"OUTER LOOP")
while j>0:
count1+=1
print(count1,"INNER LOOP")
j-=1
i-=1
#Nested for loop
count=0
count1=0
for i in range(5):
count+=1
print("\t\t",count,"OUTER LOOP")
for j in range(5):
count1+=1
print(count1,"INNER LOOP")
I am attaching the output for your reference. This code was run on Python version 3.10
OUTPUT OF NESTED WHILE LOOP [OUTPUT OF NESTED FOR LOOP][2]
1: https://i.sstatic.net/ixM2k.png [2]: https://i.sstatic.net/1vsZp.png
EDIT: Nested while loops in Python works EXACTLY like nested for loops in Python. I have edited my program in the following way:
#Nested while loop
i=5
j=5
count=0
count1=0
while i>0:
count+=1
print("\t\t",count,"OUTER LOOP")
while j>0:
count1+=1
print(count1,"INNER LOOP")
j-=1
break #Adding jump statement stops the iteration of inner loop and the outer loop gets executed again.
i-=1
