/* a6-3-1.c */
#include <stdio.h>
#include <ctype.h>

int main(void)
{
	int ch;

	for (ch = 0; ch <= 127; ch++) {
		if (isprint(ch)) {
			if (isalnum(ch)) {
				printf("%c", ch);
			}
			else {
				printf("[%c]", ch);
			}
		}
	}

	return 0;
}
