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

char*mmap();
char wbuf[1<<28],*wp=wbuf;

int l[20];

void f(i,a,b){
	if(i<0) return;
	int v=l[i];
	if(v<a|v>=b){
		f(i-1,a,b);
	}else{
		f(i-1,v,b);
		int c;
		if(c=v>>24&255) *wp++=c;
		if(c=v>>16&255) *wp++=c;
		if(c=v>>8 &255) *wp++=c;
		if(c=v>>0 &255) *wp++=c;
		*wp++=32;
		f(i-1,a,v);
	}
}

main(){
	char*rp=mmap(0l,1l<<28,1,2,0,0ll);

	while(*rp++>=48);
	do{
		while(*rp++>=48);
		int k=0,c;
		do{
			int lk=0;
			while(c=*rp++,c>=48) lk=lk<<8|c;
			l[k++]=lk;
		}while(c!=10);
		f(k-1,0,0x7fffffff);
		wp[-1]=10;
	}while(*rp);

	write(1,wbuf,wp-wbuf);
	_exit(0);
}