String►Equ("0",Y₁) Disp "Enter S to Stop" While 1 Input "Y=",Str1 If Str1="S" Stop Input "If ",Str2 If Str2="S" Stop Equ►String(Y₁,Str3) String►Equ(Str3+"+("+Str1+")("+Str2+")",Y₁) End