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

int main(int argc, char **argv) {
	char c1, c2, c3, u1, u2, u3;

	if(argc!=2) {
		printf("Usage: %s <mac address>\n", argv[0]);
		exit(1);
	}

	sscanf(argv[1], "%02hhx:%02hhx:%02hhx:%02hhx:%02hhx:%02hhx", &c1, &c2, &c3, &u1, &u2, &u3);

	// add multicast flag
	c1 |= 0x2;

	printf("fe80::%02hhx%02hhx:%02hhxff:fe%02hhx:%02hhx%02hhx/64\n", c1, c2, c3, u1, u2, u3);

	return 0;
}