flow.size: 8
row.1: 6,2,0,0,0,0,0,0
row.2: 0,8,0,0,0,0,0,0
row.3: 0,0,0,1,0,1,0,0
row.4: 0,0,0,0,4,6,0,0
row.5: 0,0,0,0,3,5,0,0
row.6: 0,0,0,0,0,3,5,2
row.7: 0,8,0,0,0,0,0,0
row.8: 0,0,0,7,0,0,7,4












