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#include <stdio.h>
#include <stdarg.h>
#include "printf.h"
int
main()
{
my_printf("str: %s\nchr: %c\nhex: %x\nint: %d\noct: %o",
"hi", 'a', 0x32, 10, 8);
return 0;
}
void
my_printf(char *format, ...)
{
char *c; // a char in the `format` string
va_list args;
va_start(args, format);
for (c = format; *c != '\0'; c++)
{
while (*c != '%')
{
putchar(*c);
c++;
}
c++;
switch(*c)
{
case 'c':
{
putchar(va_arg(args, int));
putchar('\n');
break;
}
case 'd':
{
puts(convert(va_arg(args, int), 10));
break;
}
case 'o':
{
puts(convert(va_arg(args, unsigned int), 8));
break;
}
case 'x':
{
puts(convert(va_arg(args, unsigned int), 16));
break;
}
case 's':
{
puts(va_arg(args, char*));
break;
}
}
}
va_end(args);
}
char*
convert(unsigned int num, int base)
{
static char rep[]= "0123456789ABCDEF";
static char buffer[50];
char *ptr;
ptr = &buffer[49];
*ptr = '\0';
do {
*--ptr = rep[num%base];
num /= base;
} while (num != 0);
return(ptr);
}
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