Jamgreen - 19 days ago 6

Javascript Question

I have a graph with nodes A, B, C and multiple edges between these nodes.

How can I get the unique pairs (A, B), (A, C), (B, C)?

One algorithm could be to say

`alreadyVisited = [];`

for left in nodes:

for right in nodes:

if (left, right) not in alreadyVisited:

alreadyVisited.push((left, right))

..

but is this the most efficient algorithm to achieve this?

Answer

You could iterate the nodes and iterates in a nested loop only the rest of the nodes.

```
var nodes = ['A', 'B', 'C'],
i, j,
edges = [];
for (i = 0; i < nodes.length - 1; i++) {
for (j = i + 1; j < nodes.length; j++) {
edges.push([nodes[i], nodes[j]]);
}
}
console.log(edges);
```