ForLoop.md

Loop Statement

Python supports two types of loops

1. For
2. While

For Loop

• For loop iterate over a given sequence such as list, string, tuple dictionary or any iterable object.
• For loops can iterate over a sequence of numbers using the range and xrange functions.

Syntax:

for variable in (iterable object) :
  print(variable)

Normally for range function contain three different parameter

1. starting number
2. Stop number+1
3. difference or step number(optional if not given then it will increment by 1)

Example 1 if you want to print 0 to 10 numbers using for loop

for i in range(11):
  print(i)

Output:

0
1
2
3
4
5
6
7
8
9
10

If we do not give the starting number and difference by default range function start from 0 and increment it by 1 until the given number.

Example 2 if you want to print 2 to 20 with difference 2

for i  in range(2,21,2):
  print(i)
  

Output:

2
4
6
8
10
12
14
16
18
20

range function consider starting given no as it is (include starting number as it is given) but exclude stop number so we always provide ending number by incrementing 1.

For Loop on String

if you want to print every character or alphanumeric values as one by one we can easily print using for loop.

mystring="I am python student"
for st in mystring:
  print(st)

Output:

I
 
a
m
 
p
y
t
h
o
n
 
s
t
u
d
e
n
t

For loop on List

mylst=[4,6,3,9,3]
for i in mylst:
  print(i)

Output:

4
6
3
9
3

Some Examples On For Loop

prints out the numbers 0,1,2,3,4,5,6

for x in range(7):
  print(x)

Output:

0
1
2
3
4
5
6

prints out 2,3,4,5,6,7

for x in range(2, 8):
  print(x)

Output:

2
3
4
5
6
7

prints out 3,6,9

for x in range(3, 11, 3):
  print(x)

Output:

3
6
9