7
45
1
3
(1,2,2,10)
(1,4,1,15)
(1,3,4,3)
(4,3,2,20)
(3,6,5,10)
(4,6,8,1)
(2,4,3,50)
(4,5,2,100)
(4,7,4,10)
(2,5,10,20)
(5,7,6,15)
(7,6,1,15)