#ifndef _UTIL_H_
#define _UTIL_H_

//char Hex2Char(int i);
//int Char2Hex(char c);

int Hex2Char(int fromi,char * toc);
int Char2Hex(char fromc,int * toi);

int Bitstr2ByteArr(char * bs,char * ba);
int ByteArr2Bitstr(char * ba,char * bs);

int Int2ByteArr(int i,char * ba);
int ByteArr2Int(char * ba,int * i);

#endif

#include<stdio.h>
#include"utils.h"
char Hstr[16] = {'0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F'};

int Hex2Char(int fromi,char *toc) {
	if(fromi>=0&&fromi<=9) {
		*toc= fromi+'0';
	} else if(fromi>=10&&fromi<=15) {
		*toc = fromi+'A'-10;
	} else {
		printf("error\n");
	}
	return 0;
}
int Char2Hex(char fromc,int *toi) {
	if(fromc>='0'&& fromc<='9') {
		*toi= fromc-'0';
	} else if(fromc>='A'&& fromc<='F') {
		*toi= fromc-'A'+10;

	} else {
		printf("error\n");
	}
	return 0;
}

#include<stdio.h>

#include"utils.h"

int main() {

	int n1,n2;

	char c1,c2;

	printf("请输入一个0~15的数：");

	scanf("%d",&n1);

	Hex2Char(n1,&c1);

	printf("对应的16进制字符是%c\n",c1);

	printf("请输入一个16进制字符：");

	scanf("%s",&c2);

	Char2Hex(c2,&n2);

	printf("对应的数是%d\n",n2);

}