Something

#include <iostream>
#include <cstdio>
#include <cstdlib>

#ifdef WIN32
#    include <conio.h>
#    define clrscr() system("cls")
#    define pause() getch()
#else
#    define clrscr() printf("\033c")
#    define pause() getchar()
#endif

char *getline();
char *toBinary(char *);
char *reverse(char *);

int main(int argc, char *argv[]) {
    while(1) {
        clrscr();
        printf("\n%s", toBinary(getline()));
        pause();
    }
    
    return EXIT_SUCCESS;
}

char *getline() {
    char *buf = NULL, tmp[] = " ";
    
    while((tmp[0] = getc(stdin)) != '\n' && tmp[0] != EOF) {
        buf = (char *)realloc(buf, ((buf)?strlen(buf):0) + 2);
        strcat(buf, tmp);
    }
    
    return buf;
}

char *toBinary(char *str) {
    unsigned short ch;
    char *buf = " ";
    
    
    
    for(int i=0;i<strlen(str);i++) {
        ch = str[i];
        
        while(ch > 0) {
            buf = (char *)realloc(buf, ((buf)?strlen(buf):0) + 2);
            strcat(buf, (ch%2)?"1":"0");
            ch /= 2;
        }
        
    }
    
    return reverse(buf);
}

char *reverse(char *str) {
    char *buf = (char *)malloc(strlen(str) + 1), tmp[] = " ";
    
    for(int i=strlen(str)-1;i>=0;i--) {
        tmp[0] = str[i];
        strcat(buf, tmp);
    }
    
    return buf;
}