Editing Persistent data structure (section)

===CHANGE-EDGE===
If we assume that CHANGE-EDGE({{mvar|v}}, {{mvar|i}}, {{mvar|u}}) is called, then there are two cases to consider. 
* There is an empty row in the table of the vertex {{mvar|v}}: In this case we copy the last row in the table and we change the {{ord|{{mvar|i}}}} edge of vertex {{mvar|v}} to point to the new vertex {{mvar|u}}
* Table of the vertex {{mvar|v}} is full: In this case we need to create a new table. We copy the last row of the old table into the new table. We need to loop in the array inedges({{mvar|v}}) in order to let each vertex in the array point to the new table created. In addition to that, we need to change the entry {{mvar|v}} in the inedges(w) for every vertex {{mvar|w}} such that edge {{mvar|v,w}} exists in the graph {{mvar|G}}.