#pragma GCC optimize("Ofast")
#pragma GCC target("avx2")

char*mmap();

main(){
	char*rp=mmap(0l,1l<<28,1,2,0,0ll);
	while(*rp++!=10);
	char*a=rp;
	while(*rp++!=10);
	char*b=rp;

	while(*a==*b)++a,++b;
	b=a;
	while(*++b>32);
	write(1,a,b-a);
	_exit(0);
}