Question

c++

Develop a program that validates a password entered by a user. The password must meet the following criteria:

1. Be at least six characters long.
2. Contain at least one uppercase and at least one lowercase letter.
3. Have at least one digit.

Write a program that asks for a password and then verifies that it meets the stated criteria. If it does not, the program should display a message telling the user why and ask for another password. The program should keep asking for the password until the password meets the criteria.

The validation should be done on a separate function called validation, which takes a string variable as parameter and returns an integer. It should return 0 if the password is valid and 1 if it does not match the first criteria, 2 if it does not match the second criteria and 3 if it does not match the third criteria.

Answer 1

Code:

#include <iostream>
//as we are using isupper() ,islower(),and isdigit()
//functions, we have to include this library
#include <cctype>
using namespace std;
//function named validation which takes a string named
//pass as argument and returns a int is defined
int validation(string pass){
   //length of pass
   int len=pass.length();
   //variables to store counts of uppercase,
   //lower case, and digits
   int upper_count=0;
   int lower_count=0;
   int digit_count=0;
   //traversing the string and checking each character
   //and incrementing the respective count variable
   for(int i=0;i<len;i++){
       if(isupper(pass[i])){
           upper_count++;
       }
       if(islower(pass[i])){
           lower_count++;
       }
       if(isdigit(pass[i])){
           digit_count++;
       }
   }
   //if len is lessthan 6 returning 1
   if(len<6){
       return 1;
   }
   //if either of uppercount and lowercount are lessthan 1
   //returning 2
   else if(upper_count<1 || lower_count<1){
       return 2;
   }
   //if digit_count is lessthan 1 returning 3
   else if(digit_count<1){
       return 3;
   }
   //if all of the above cases are false then return 0
   else{
       return 0;
   }
}
//main functions
int main(){
   //a string named password
   string password;
   //this loop iterates until a valid password is entered
   while(true){  
   //taking input
   cout<<"Enter password: "<<endl;
   cin>>password;
   //calling function validation with argument password
   //and storing the return value in res
   int res = validation(password);
   //showing the reason
   if(res==0){
       cout<<"password is valid"<<endl;
       break;
      
   }
   else if(res==1){
       cout<<"Password should be atleast six characters"<<endl;
   }
   else if(res==2){
       cout<<"Password should contain atleast 1 uppercase and 1 lowercase letters"<<endl;
   }
   else if(res==3){
       cout<<"Passsword should contain atleast 1 digit"<<endl;
   }
   else{
       cout<<"Invalid"<<endl;
   }
}
                  
}

Output:

Code Screenshot:

Code Snippet:

#include <iostream>
//as we are using isupper() ,islower(),and isdigit()
//functions, we have to include this library
#include <cctype>
using namespace std;
//function named validation which takes a string named
//pass as argument and returns a int is defined
int validation(string pass){
        //length of pass
        int len=pass.length();
        //variables to store counts of uppercase,
        //lower case, and digits
        int upper_count=0;
        int lower_count=0;
        int digit_count=0;
        //traversing the string and checking each character
        //and incrementing the respective count variable
        for(int i=0;i<len;i++){
                if(isupper(pass[i])){
                        upper_count++;
                }
                if(islower(pass[i])){
                        lower_count++;
                }
                if(isdigit(pass[i])){
                        digit_count++;
                }
        }
        //if len is lessthan 6 returning 1
        if(len<6){
                return 1;
        }
        //if either of uppercount and lowercount are lessthan 1
        //returning 2
        else if(upper_count<1 || lower_count<1){
                return 2;
        }
        //if digit_count is lessthan 1 returning 3
        else if(digit_count<1){
                return 3;
        }
        //if all of the above cases are false then return 0
        else{
                return 0;
        }
}
//main functions
int main(){
        //a string named password
        string password;
        //this loop iterates until a valid password is entered
        while(true){    
        //taking input
        cout<<"Enter password: "<<endl;
        cin>>password;
        //calling function validation with argument password
        //and storing the return value in res
        int res = validation(password);
        //showing the reason
        if(res==0){
                cout<<"password is valid"<<endl;
                break;  
        }
        else if(res==1){
                cout<<"Password should be atleast six characters"<<endl;
        }
        else if(res==2){
                cout<<"Password should contain atleast 1 uppercase and 1 lowercase letters"<<endl;
        }
        else if(res==3){
                cout<<"Passsword should contain atleast 1 digit"<<endl;
        }
        else{
                cout<<"Invalid"<<endl;
        }
}
                                        
}