Question

Create a C++ program which will prompt the user to enter a password continually until the password passes the following tests.

Password is 6 chars long

Password has at least 1 number

If the input does not match the tests, it will input a specific error message. "Pass must be 6 chars long."

If the input is allowed, print a message saying "Correct Password Criteria."

Answer 1

C++ Program :

#include <iostream>
using namespace std;

bool validPassword(string s)      // ensures that the password has atleast 1 number in it
{
    int count =0;
    for(int i=0; i<s.length(); i++) // iterate through all characters in string
    {
        if(s[i]>='0' && s[i]<='9') // check if characters are between 0 to 9 (contain digits)
        {
            count++;               // if it contains digits increment count
        }
    }
    if(count>0)              // return true only when there is atleast one number in password
    {
        return true;
    }
    else
    {
        return false;
    }
    
}

int main()
{
    string password;
    while(1)        // infinite loop
    {
        cout << "Please enter a password : ";  // ask for password from user
        cin >> password;
        if((password.length() == 6) && validPassword(password)) // check if password is in correct criteria
        {
            cout << "Correct Password Criteria."<<"\n";    // end the loop if we get correct criteria
            break;
        }
        else                    // print a error message saying specific error
        {
            if(password.length() != 6)        
            {
                cout << "Password must be 6 chars long.\n\n";
            }
            else
            {
                cout << "Password must have atleast 1 number.\n\n";
            }
        }
        
    }
    return 0;
}

Screenshots :