運算式 5: "x" equals "a" left brace, "g" left parenthesis, "x" , right parenthesis less than "y" less than "f" left parenthesis, "x" , right parenthesis , right bracex=agx<y<fx
5
運算式 6: "x" equals "b" left brace, "g" left parenthesis, "x" , right parenthesis less than "y" less than "f" left parenthesis, "x" , right parenthesis , right bracex=bgx<y<fx
6
運算式 7: "g" left parenthesis, "x" , right parenthesis less than "y" less than "f" left parenthesis, "x" , right parenthesis left brace, "a" less than "x" less than "b" , right bracegx<y<fxa<x<b