errorentry / display(ERROR)op_normalentry / display(OPERAND_2)op_chainedentry / display(OPERAND_1)op_enterednegated2entry / negate(op2)OPER ['-'] / ;frac2DIGIT_0 / insert(op2)DIGIT_1_9 / insert(op2)POINT / ;int2DIGIT_0 / insert(op2)DIGIT_1_9 / insert(op2)zero2DIGIT_0 / ;operand2entry / display(OPERAND_2)frac1DIGIT_0 / insert(op1)DIGIT_1_9 / insert(op1)POINT / ;int1DIGIT_0 / insert(op1)DIGIT_1_9 / insert(op1)zero1DIGIT_0 / ;operand1entry / display(OPERAND_1)resultentry / display(RESULT)beginentry / display(OPERAND_1)negated1entry / negate(op1)OPER ['-'] / ;readyonentry / op1=' 0'; op2=' 0'exit /POINTDIGIT_1_9 / insert(op2)DIGIT_0DIGIT_0DIGIT_1_9 / insert(op2)POINT / insert(op2)POINT / insert(op2)CE / op2=-' 0'OPER ['-']OPERDIGIT_1_9 / insert(op1)CE / op1=-' 0'DIGIT_0DIGIT_0DIGIT_1_9 / insert(op1)POINT / insert(op1)POINT / insert(op1)POINT / insert(op1)DIGIT_1_9 / insert(op1)POINT / insert(op2)POINT / insert(op2)DIGIT_1_9 / insert(op2)OPER[else][error][error]EQUALS /calculate()CE / op2=' 0'OPER /calculate()[else]OPER ['-']CE / op1=-' 0'C