十六进制转化二进制[c]

#include<stdio.h>
#include<string.h>
#include<stdlib.h>
int hex2dec(char c)
{
    int i=;
    //char cc[1]={0};
    //cc[0]=c;
    if(c>=''&&c<='')
        i=c-'';       //('0')48-48=0
    else if(c>='A'&&c<='Z')
        i=c-''-;    //(A)65-48-7=10
    else if(c>='a'&&c<='z')
        i=c-''-;  //(a)97-48-39=10
    //if(cc[0]>='0'&&cc[0]<='9')
 //       i=cc[0]-'0';       //('0')48-48=0
    //else if(cc[0]>='A'&&cc[0]<='Z')
    //    i=cc[0]-'0'-7;    //(A)65-48-7=10
    //else if(cc[0]<='a'&&cc[0]<='z')
    //    i=cc[0]-'0'-39;  //(a)97-48-39=10
    else
    {
        printf("error!\n");
        exit();
    }
    return i;
}
int main()
{
    int j=;
    int index=;
    char print[]={};
    char *str[]=
    {
        "","","","",    //0-3
        "","","","",    //4-7
        "","","","",    //8-11
        "","","",""     //12-15
    };
    char hex[];
    while ()
    {
        scanf("%s",hex);
        for(j=strlen(hex)-;j>=;j--)
        {
            index=hex2dec(hex[j]);
            strcat(print,str[index]);
            strcat(print," ");
        }
        printf("%s转化结果:%s\n",hex,print);
        memset(print,,);
    }

}