Checking for Digit using if else – Computer Sir Ki Class

Checking for Digit using if else – Computer Sir Ki Class

Code Learning #CPP#1865

Checking for Digit using if else

Collecting a char input and checking the input as a digit or a non-digit.

Learning Objectives

Learning the range check for a digit.
Learning to find an alternate path when given selection condition is not true using the else keyword.

Program Approach

A digit would be essentially in the range of 0 to 9 so the condition check will be formed as character greater or equal to ‘0’ and lesser or equal to ‘9’.

Source Code

Run Output

Enter a character : 5

You entered a digit



-OR-

Enter a character : a

Character you entered was not a digit

Code Understanding

char d; cout<<“Enter a character : “; cin>>d;
Here we collect the input as a single character from the user.

if(d >= ‘0’ && d<=’9′)
Here we check if the character entered is between the range 0 to 9 as all the digit characters are supposed to be in that range only.

cout<<“You entered a digit”<<endl;
Here we print the message announcing that the number entered by the user was a digit.

else
This one is to give an alternate selection path when given condition of checking for digit is not true.

cout<<“Character you entered was not a digit”<<endl;
When the given condition is not true this message is printed.

Notes

For digit check one can also check using the ascii value 48 to 57. The same condition may also be written like if( d>= 48 && d<=57).

Suggested Filename(s): checkdigit.cpp

sunmitra| Created: 22-Dec-2017 | Updated: 15-Sep-2018|

Post Views: 429

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