To Check Strength of a Password using C Program.

1. TO CHECK
STRENGTH OF
A PASSWORD
USING C
PROGRAM

2. Problem Statement

3. Write a C program that checks if a given
password is strong,weak or moderate as per
the rules given below:
 If it contains combination of digits, alphabets and special
characters, then the password is strong.
 If it contains a combination of only digits and alphabets, then
the password is moderate.
 If it contains only alphabets, then the password is weak.
3

4. Theory

5.  This Program is used to check whether the given Password is Strong, Moderate or
Weak depending upon elements of password. For this we have used multiway
condition statement. i.e., else if ladder.
 Syntax of if else ladder:-
if(Condition 1)
{
Statement 1;
}
else if(Condition 2)
{
Statement 2;
}
else
{
Statement n;
}

6. Algorithm

7. Step 1: Start
Step 2: Read Password
Step 3: for i=0 to password[i]=‘0’
if(password contains alphabets)
alpha++
else if(password contains digits)
digit++
else
special++
Step 4: Print using for loop.
Step 5: Stop

8. Implementation Of Logic

9. Firstly Password will be inputed by the user and
stored in the variable ‘password’ in the program then
the password is checked whether it contains
alphabets, special characters and digits, if true then
password is Strong, if false then the next condition is
checked whether the password contains alphabets
and digits, if true then password is Moderate, if false
then the password will be declared as Weak.

10. Program

11. #include<stdio.h>
#include<string.h>
#include<ctype.h>
main()
{
char password[100],alpha,digit,special,i;
printf("Enter your Passwordn");
gets(password);
for(i=0; password[i]!=‘0’; i++)
{
if(isalpha(password[i])!=0)
alpha++;
else if(isdigit(password[i]!=0)
digit++;
else
special++;
}
{
if(alpha>0 && digit>0 && special>0)
printf(“Great! Your password is strongn”);
else if(alpha>0 && digit>0)
printf(“Your password is moderaten We recommend you to add some special
charactersn”);
else
printf(“your password is Weak! Please Enter againn”);
}

12. Manual Calculation

13. Case 1:-
Read, password=hunkingSTAR@9
if(isalpha(password[i])!=0)
alpha++;
else if(isdigit(password[i]!=0)
digit++;
else
special++;
Print ‘Your password is Strong.’
Case 2:-
Read, password=hunkingSTAR9
if(isalpha(password[i])!=0)
alpha++;
else if(isdigit(password[i]!=0)
digit++;
else
special++;
Print ‘your password is Moderate.

14. MADE BY NAVEENCHANDRA HALEMANI
nhalemani@gmail.com