Next, for each number in the sequence a[i], find the first (lowest-numbered) node, j, with degree equal to 1, add the edge (j, a[i]) to the tree, and decrement the degrees of j and a[i]. In pseudo-code:

8 for each value in do 9 for each node in do 10 if degree[] = 1 then 11 Insert edge[, ] into 12 degree[] <- degree[] - 1 13 degree[] <- degree[] - 1 14 break