#include <iostream>
using namespace std;

int main()
{
	const int MAX_COORDINATE = 10000;
	int skyline[MAX_COORDINATE]={0};
	while(cin.eof()!=0)
	{
		int L,H,R;
		cin>>L>>H>>R;
		for(int x=L;x<R;x++)
		{
			if(H>skyline[x])
			{
				skyline[x]=H;
			}
		}
	}

	bool firstOne=true;
	int lastHeight=0;
	for(int x=0;x<MAX_COORDINATE;x++)
	{
		if( skyline[x]!=lastHeight )
		{
			if(firstOne)
			{
				cout<<x<<" "<<skyline[x];
			}
			else
			{
				cout<<" "<<x<<" "<<skyline[x];
			}
		}
	}
	return 0;
}