Module Ext_scc

Assume input is int array with offset from 0 Typical input

[|
  [ 1 ; 2 ]; // 0 -> 1,  0 -> 2 
  [ 1 ];   // 0 -> 1 
  [ 2 ]  // 0 -> 2 
|]

Note that we can tell how many nodes by calculating Array.length of the input

Used for unit test