How to return a external sentences for a loop ?

Hi, I try to realize a program for this flowchart but, I had problem with the part that I marked in red. The problem is in the part that it defined for second time "sigma less or equal 0" I don't know how to create the code for this part.

In mi code, when It defined in first time "sigma less or equal 0", I use the sentences 'if' and break if the sentences is fulfilled then,I use "else" and "while" (in the part I defined sigma more or equal 0") for the next part. I appreciate your answer!

Answer 1

[Walter Roberson]

while true
  do a calculation
  if conditions are good
     break
  end
  do another calculation
  if conditions are good
     break
  end
end
do the final calculations