(B13) Python Part7 For loop - Break ,Continue and Pass

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Python For Loops
A for loop is used for iterating over a sequence (that is either a list,
a tuple, a dictionary, a set, or a string).

This is less like the for keyword in other programming languages, and
works more like an iterator method as found in other object-orientated
programming languages.

With the for loop we can execute a set of statements, once for each item
in a list, tuple, set etc.

Example
Print each fruit in a fruit list:

fruits = ["apple", "banana", "cherry"]
for x in fruits:
print(x)


for x in "Vedicsoft":
print(x)

Output:
V
e
d
i
c
s
o
f
t

list1=[23,44,16,71,49,52]
for a in list1:
print(a)

---
break: With the break statement we can stop the loop before it has looped through all the items
continue :With the continue statement we can stop the current iteration of the loop, and continue with the next
pass:
list1=[23,44,16,71,49,52]
for a in list1:
if a == 16:
break
print("a=",a)

print("Bye!")

Output:



list1=[23,44,16,71,49,52]
for a in list1:
if a == 16:
continue
print("a=",a)

print("Bye!")

Output:


list1=[23,44,16,71,49,52]
for a in list1:
if a == 16:
print("Skipped a=",a)
continue
print("a=",a)

print("Bye!")

output:
a= 23
a= 44
Skipped a= 16
a= 71
a= 49
a= 52
Bye!

list1=[23,44,16,71,49,52]
for a in list1:
if a == 16:
print("pass at a=",a)
pass
print("a=",a)

print("Bye!")

a= 23
a= 44
pass at a= 16
a= 16
a= 71
a= 49
a= 52
Bye!
--------------------------------
The range() Function
To loop through a set of code a specified number of times, we can use
the range() function,
The range() function returns a sequence of numbers, starting from 0 by
default, and increments by 1 (by default), and ends at a specified number.

for a in range(5):
print(a)

print("bye!")

for a in range(5,101):
print(a)

print("bye!")

for a in range(5,101,10):
print(a)

print("bye!")

for a in range(1,11):
print(3,'x',a,'=',a*2)

print("bye!")

3 x 1 = 2
3 x 2 = 4
3 x 3 = 6
3 x 4 = 8
3 x 5 = 10
3 x 6 = 12
3 x 7 = 14
3 x 8 = 16
3 x 9 = 18
3 x 10 = 20
bye!
-----------------------------------
for a in range(1,11):
print(3,'x',a,'=',a*2)
else:
print("3rd table")
print("bye!")
-----------------------------
for a in range(1,11):
if a % 2 == 0:
print("even numbers=",a)
else:
print("odd numbers=",a)

print("bye!")
----------------------------
for loops cannot be empty, but if you for some reason have a
for loop with no content, put in the pass statement to avoid
getting an error.

for a in range(1,11):
pass
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