Introduction - If you have any usage issues, please Google them yourself
Pairs of PL/0 expansion of the original code to make the following changes: Add the word: reserved word ELSE, REPEAT, UNTIL, RETURN operator+=,-=,++,-- (2) modify the words: inequality# changed to " " (3 ) increasing the conditional statement of the ELSE clause (a) expanding the assignment operator:+ = and-= (2) Expansion statement REPEAT < statement sequence> UNTIL < terms of " where" condition " is cyclical conditions, namely the conditions are not set up, repeat loop body " statement sequence" condition is when the cycle ended. Increase the operation:++ and-.