#include <stdio.h>
#include <stdlib.h>

main(int argc, char *argv[]) {
	int c;
	FILE *fp = stdin;

	if (argc > 1)
		fp = fopen(argv[1], "r");
	if (fp == NULL) {
		fprintf(stderr, "can't open %s\n", argv[1]);
		exit(1);
	}
	while ((c = getc(fp)) != EOF)
		putc(c, stdout);
}