Simple coversion program hanging on input

[abhishekcoder]

Dear All,


I have written a code to implement an algorithm for base conversion from decimal to any base between 2 and 36 given in RG Dromey. Below is my code and I have a few questions relating to it:

#include<stdio.h>
#include<stdlib.h>
int main()
{
    int newbase,zero=atoi(0),q,ndigit=0,r,ascii,i;
    char newrep[100];
    printf("Enter number and base(between 0 and 36) to be converted");
    scanf("%d%d",&q,&newbase);
    while(q!=0)
    {
    r=q%newbase;
    ndigit+=1;
    ascii=zero+r;
    if(ascii>atoi(9))
    {
                      ascii=ascii+7;
    }
    newrep[ndigit]=(char)ascii;
    q=q/newbase;
    }
    for(i=ndigit;i<=1;i++)
    {
    printf("%d",newrep[ndigit]);
    }
    system("pause");
    return 0;       
}

1. Why is there a need for reverse conversion to characters of the ascii value after conversion before storing them in the array newrep.
2. My program hangs when I input the values of q and newbase on dev C platform. Please help!

[Subsonics]

1. Why is there a need for reverse conversion to characters of the ascii value after conversion before storing them in the array newrep.
2. My program hangs when I input the values of q and newbase on dev C platform. Please help!

1. it isn't unless you decide to store each individual digits in the array as ascii characters.

2. All your atoi calls will cause segfaults, it expects a string not an integer. But the use of atoi for this is pointless since atoi("0") will return 0 so you can just assign 0 directly to 'zero', ditto for the rest where atoi is used. There are lot's of other problem too, you overwrite 'ascii' in each iteration of the loop for one. Edit: actually you don't but your indentation makes that hard to see.

Some more comments:

If you want to represent numbers above 9 with letters from a - z, you can assign the ascii value directly with a single quote around it, example: zero = '0'

On line 12 you update your index before you use the array so, it will actually be indexed from 1 not from 0

The last for loop does not make sense in any way, you want to print each character in the array, so start from your first index 0 (1 in your current case) and use ndigit as ending condition. In the loop you want to print characters so: %c should be used in the format string.