LFS Forum - A little help please

#1 - niall09

A little help please

Sat 3 Nov 2007, 17:45

Hi

Im very new to programming and i just need a little help

This is a little (very basic) app that solves quadratic equations

I want to add a bit on to it, but my basic skills are letting me down. Where it says "No Solution", i would like to add a bit where it says "No solution, would you like another go?" then if they say yes, it goes to the beginning and if they say no, the program exits.

I hope i explained it well enough

Thanks

#include <stdio.h>
#include <math.h>
int main()
{
     //declare variables
     double a,b,c,x1,x2,d;
     
     //read inputs
     printf("What number represents a?  "); scanf("%lf",&a);
     printf("What number represents b?  "); scanf("%lf",&b);
     printf("What number represents c?  "); scanf("%lf",&c);
     
     //calculate x1,x2
     d=b*b-4*a*c;
     if(d>=0)
     {
             x1=(-b+sqrt(d))/(2*a);
             x2=(-b-sqrt(d))/(2*a);
             printf("x1=%d\n",x1);
             printf("x2=%d\n",x2);
     }
             else
             {
                 printf("No solution\n");
             }
}

#2 - the_angry_angel

Sat 3 Nov 2007, 18:51

Untested, but baring any typos, it should be fine. Things to note; 'yes' is case sensitive here, fgets is used in place of gets to avoid an overflow. Because of this, we use 'stdin' is the file descriptor for standard input.

#include <stdio.h>
#include <string.h>
#include <math.h>
int main()
{
    //declare variables
    double a,b,c,x1,x2,d;

    unsigned char solution = 0;
    
    while (solution == 0)
    {
        //read inputs
        printf("What number represents a?  ");
        scanf("%lf",&a);
        printf("What number represents b?  ");
        scanf("%lf",&b);
        printf("What number represents c?  ");
        scanf("%lf",&c);
    
        //calculate x1,x2
        d=b*b-4*a*c;
        if(d>=0)
        {
            x1=(-b+sqrt(d))/(2*a);
            x2=(-b-sqrt(d))/(2*a);
            printf("x1=%d\n",x1);
            printf("x2=%d\n",x2);
        }
        else
        {
            printf("No solution, do you wish to try again?\nPlease enter 'yes' to retry.\n");
            char input[6];
            memset(input, 0, 6);
            fgets(input, 6, stdin);
            if (strncmp(input, "yes", 6) == 0)
                solution = 1;
        }
    }

    printf("Goodbye!\n");
    return 0;
}

#3 - niall09

Sat 3 Nov 2007, 18:56

Thanks alot

Very much appreciated

#4 - niall09

Sat 10 Nov 2007, 18:17

Hi again,

I need help again, but this time its HTML help.

How do I get the <button> command to link to another page. I have looked at a few websites but I can't find much on it.

Thanks

EDIT: I found out how to do it

#5 - DarkTimes

Sat 10 Nov 2007, 18:43


<input 
    type = "button" 
    onclick = "window.location='http://www.somewhere.com/';" 
    value = "Click me" />

Something like that should do it.

Edit: Just thinking, for a non-JavaScript version you could do something like this:


<form action="http://www.somewhere.com/">
<input type="submit" value="Click me" />
</form>

#6 - niall09

Sat 10 Nov 2007, 18:54

Quote :
Edit: Just thinking, for a non-JavaScript version you could do something like this:


<form action="http://www.somewhere.com/">
<input type="submit" value="Click me" />
</form>

Yeah, i done it this way