Description

There are K line segments on a plane. These are all segments of a broken line, in arbitrary order. Write a program to check whether the broken line is closed.

Input

Input data is in (4*K+1) lines, each of them consists of no more then 250 characters. The first line of the file contains the number of segments K (1≤K≤3000). Each segment is described by the coordinates X’, Y’, X’’, and Y’’ of its end-points. All coordinates are non-negatives integers and written in separate lines (so, the coordinates of one segment are in four sequential lines).

Output

The first and only line of the file must contain the number 1 if the broken line is closed, and 0 otherwise.

3
0
0
0
1
1
0
0
0
1
0
0
1

1

Source

Northeastern Europe 2002, Western Subregion