DouKaku?

#include <stdio.h>
#include <string.h>

#define QWORD unsigned long long
#define DWORD unsigned long
#define WORD  unsigned short
#define BYTE  char

void conv_byte(char *p,QWORD n){
    int m,i=7;strcpy(p,"0B");
    if(n)while(i--)p+=(m=(n>>10*i)&1023)?sprintf(p,"%d%c",m,"BKMGTPE"[i]):i?0:sprintf(p,"B");
}

void conv_put(char *buf,QWORD n){
    conv_byte(buf,n);
    printf("%Ld=%s\n",n,buf);    
}

int main(){
    char buf[64];
    
    conv_put(buf,(QWORD)-1);
    conv_put(buf,(DWORD)-1);
    conv_put(buf,(WORD)-1);
    conv_put(buf,(BYTE)-1);
    conv_put(buf,0);

    conv_put(buf,(QWORD)1024*1024*1024*1024*1024*1024);
    conv_put(buf,(QWORD)1024*1024*1024*1024*1024);
    conv_put(buf,(QWORD)1024*1024*1024*1024);
    conv_put(buf,(QWORD)1024*1024*1024);
    conv_put(buf,(QWORD)1024*1024);
    conv_put(buf,(QWORD)1024);
    conv_put(buf,(QWORD)1);

    return 0;
}