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Password Creator Checker

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Join Date: Apr 2009

Posts: 22

Reputation: moiron is an unknown quantity at this point

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moiron

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Newbie Poster

Password Creator Checker

May 5th, 2009

i need help making a password program. it lets the use input a password and check it if it is following the password rules, which are the following:

must have exactly 7 characters, only alphabets and digits are allowed.

i don't exactly know how to put that in an if else function, but i know i have to use that.

i also don't know if the string.h library is needed but, in our book, the question was from a chapter with strings.

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Join Date: Feb 2008

Posts: 1,602

Reputation: jephthah has much to be proud of

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jephthah

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Posting Virtuoso

Re: Password Creator Checker

May 5th, 2009

use "strlen" and check character ranges. look at your ascii table.

post some code if you want any more advice.

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Join Date: Apr 2009

Posts: 22

Reputation: moiron is an unknown quantity at this point

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moiron

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Newbie Poster

Re: Password Creator Checker

May 5th, 2009

i guess i can use that to check the length, and use the if else to see if the length is exactly 7.
and since the password is supposed to be 7 would i need to make the array size 8 for the \0 part of the string?

since u told me to post a code im gonna try but i know its wrong.

 Help with Code Tags 
 C Syntax (Toggle Plain Text) 
#include <stdio.h>
#include <string.h>
 
int main (void)
{
	int length;
	char pass[8];
	printf("Enter a password with 8 characters.");
	printf("It must have at least 1 digit and 1 alphabet.");
 
	fgets( pass, 8, stdin);
#include <stdio.h>
#include <string.h>

int main (void)
{
	int length;
	char pass[8];
	printf("Enter a password with 8 characters.");
	printf("It must have at least 1 digit and 1 alphabet.");

	fgets( pass, 8, stdin);

that's what i have for now, im trying to add the if function with strlen in it

Last edited by moiron; May 5th, 2009 at 5:38 pm.

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Join Date: Aug 2005

Posts: 239

Reputation: extofer is an unknown quantity at this point

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extofer

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Posting Whiz in Training

Re: Password Creator Checker

-1

May 5th, 2009

Use the length() function and return a boolean

string str ("pasword");

if str.length() < 7 {
return 0;
}
else{
return 1:
}

Last edited by extofer; May 5th, 2009 at 6:07 pm.

Gabriel Villa
software development/ IT support consultant

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Join Date: Feb 2008

Posts: 1,602

Reputation: jephthah has much to be proud of

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jephthah

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Posting Virtuoso

Re: Password Creator Checker

May 5th, 2009

that doesnt help him if his password is supposed to be EXACTLY seven characters, now does it?

and this is C, not C++

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Join Date: May 2006

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WaltP

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Posting Sensei

Re: Password Creator Checker

May 6th, 2009

After reading in the password call functions to test each individual rule. Don't try to test all things in one function, or ghod forbid right after the read.

The 3 Laws of the Procrastination Society:
1) Never do today that which can be put off until tomorrow
2) Tomorrow never comes

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Join Date: Mar 2009

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Reputation: dmachop is an unknown quantity at this point

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dmachop

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Newbie Poster

Re: Password Creator Checker

May 8th, 2009

 Help with Code Tags 
 C Syntax (Toggle Plain Text) 
#include<stdio.h>
#include<string.h>
 
int main()
{
char un[7],pwd[10];
int i,f;
printf("\nEnter user name and pwd");
scanf("%s%s",un,pwd);
if(strlen(un)==7)
{
for(i=0;i<strlen(pwd);i++)
{
if(!isalnum(pwd[i]))
f=1;
}
}
if(f==1)
printf("pwd error");
else
-------proceed---------------
}
#include<stdio.h>
#include<string.h>

int main()
{
char un[7],pwd[10];
int i,f;
printf("\nEnter user name and pwd");
scanf("%s%s",un,pwd);
if(strlen(un)==7)
{
for(i=0;i<strlen(pwd);i++)
{
if(!isalnum(pwd[i]))
f=1;
}
}
if(f==1)
printf("pwd error");
else
-------proceed---------------
}