/*
 * leb36 - little endian, base 36 increment exercise.  27 aug 2003.
 *
 * 	feel free to cut and paste this code as you wish.
 */

#include <stdio.h>

int main( int argc, char **argv ) {

	FILE * fi;
	char num[ 3 ];
	char i;

	fi = fopen( "xx36", "r+" );
	/* (the file "xx36" needs to exist and have been 
	 * initialized to have "000" as the first three
	 * characters before you run this program.)
	 */
	fread( num, 1, 3, fi );

	for ( i = 0; i < 3; i++ ) {
		if ( num[ i ] == 'z' ) {
			num[ i ] = '0';
		} else {
			if ( num[ i ] == '9' ) {
				num[ i ] = 'a';
			} else {
				num[ i ]++;
			}
			break;
		}
	}

	fseek( fi, 0, SEEK_SET );
	fwrite( num, 1, 3, fi );
	
	return 0;

}