#include "stdio.h"
#include"string.h"
static char hexnum[10];
void reverse(char *str)
{
char *pBegin=str,*pEnd=str,tmp;
while(*pEnd)
pEnd++;
pEnd--;
for(;pBegin<pEnd;pBegin++,pEnd--)
tmp=*pBegin,*pBegin=*pEnd,*pEnd=tmp;
}
char *itoh(int num)
{
int hex,i=0;
char hexnum[10];
for(;num/=16;i++)
{
hex=num%16;
hexnum[i]=(hex<=9)?hex+'0':hex-10+'a';
}
reverse(hexnum);
return hexnum;
}
void main(void)
{
printf("hex(%d)=%s\n",18,itoh(18));
}