1.If any di>=n then fail
2.If there is an odd number of odd degrees then fail
3.If there is a di<0 then fail
4.If all di=0 then report success
5.Reorder S into non-increasing order
6.Let k=d1
7.Remove d1 from S
8.Subtract 1 from the first k terms remaining of the new sequence
9.Go to step 3 above