original graph:
0 <--> 3 3 2 
1 <--> 3 
2 <--> 0 3 
3 <--> 0 0 1 2 
1(0,3) 2(0,3) 3(1,3) 4(2,0) 5(3,2) 

removing edges connecting 0 and 3
0 <--> 2 
1 <--> 3 
2 <--> 0 3 
3 <--> 1 2 
3(1,3) 4(2,0) 5(3,2) 
removing edges with weight greater than 3
0 <--> 
1 <--> 3 
2 <--> 
3 <--> 1 
3(1,3)