Start New Discussion within our **Software Development Community** # Decimal to Base 2 - 16 Conversion

```
// Convert a positive decimal integer to a number of base (2 to 16)
// Also a good example for using do ... while() to check input
// tested with Pelles C vegaseat 1dec2004
#include <stdio.h>
char *conv_base(long number, int base);
int main()
{
int base;
long number;
char yn;
do
{
do
{
printf("\n\nEnter an integer number : ");
scanf("%ld",&number);
} while (number < 1); // positive integers only
do
{
printf("\nEnter the base (2-16) : ");
scanf("%d",&base);
} while (base < 2 || base > 16); // stay in range
printf("\nThe converted number is : %s",conv_base(number,base));
printf("\n\n Any more (y/n) : ");
getchar(); // a little goofy but needed
yn = getchar();
} while (!(yn == 'n' || yn == 'N'));
return 0;
}
char *conv_base(long number, int base)
{
long remain;
int n = 0, k = 0;
static char temp[32], result[32];
static char *digit = "0123456789ABCDEF"; // list of digits
do
{
remain = number % base; // modulo gets remainder
number = number / base; // whittle down number
temp[k++] = digit[remain];
} while (number > 0);
while (k >= 0)
{
result[n++] = temp[--k]; // spell forward
}
result[n-1] = 0; // add string EOS
return (result);
}
```

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