Accessing characters in a String

Accessing characters in a String

Once you define a string, python allocate an index value for its each character. These index values are otherwise called as subscript which are used to access and manipulate the strings. The subscript can be positive or negative integer numbers.

The positive subscript 0 is assigned to the first character and n-1 to the last character, where n is the number of characters in the string. The negative index assigned from the last character to the first character in reverse order begins with -1.

Example

Example 1 : Program to access each character with its positive subscript of a giving string

str1 = input ("Enter a string: ")

index=0

for i in str1:

print ("Subscript[",index,"] : ", i)

index + = 1

Output

Enter a string: welcome

Subscript [ 0 ] : w

Subscript [ 1 ] : e

Subscript [ 2 ] : l

Subscript [ 3 ] : c

Subscript [ 4 ] : o

Subscript [ 5 ] : m

Subscript [ 6 ] : e

Example 2 : Program to access each character with its negative subscript of a giving string

str1 = input ("Enter a string: ")

index=-1

while index >= -(len(str1)):

print ("Subscript[",index,"] : " + str1[index])

index += -1

Output

Enter a string: welcome

Subscript [ -1 ] : e

Subscript [ -2 ] : m

Subscript [ -3 ] : o

Subscript [ -4 ] : c

Subscript [ -5 ] : l

Subscript [ -6 ] : e

Subscript [ -7 ] : w