capacity	flow on arc	arc connecting the nodes			
6	6	1.2	kirchhoff's conditions:	IN	OUT
4	4	1.3	node 2	6	6
1	1	2.3	node 3	5	5
4	4	2.4	node 4	5	5
2	1	2.5	node 5	5	5
1	1	3.4			
6	4	3.5			
3	0	4.5	flow size	10	
6	5	4.6			
5	5	5.6