Java programming homework. Please help.Need help with exercise P 6.35: C-6.19 Postfix notation is an unambiguous way of writing an arithmetic expression with-out parentheses. It is defined so that if "(exp₁) op (exp2)" is a normal fully paren-thesized expression whose operation is op, the postfix version of this is "pexp₁pexp2 op", where pexp₁ is the postfix version of exp₁ and pexp2 is the postfix ver-sion of exp2. The postfix version of a single number or variable is just that numberor variable. So, for example, the postfix version of "((5+2) * (8 − 3))/4" is "5* 4 /". Describe a nonrecursive way of evaluating an expression inpostfix notation.2+83- P-6.35 Implement a program that can input an expression in postfix notation (see Exer-cise C-6.19) and output its value.

Answered: P-6.35 Implement a program that can…

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Java programming homework. Please help.

Need help with exercise P 6.35:

C-6.19 Postfix notation is an unambiguous way of writing an arithmetic expression with-
out parentheses. It is defined so that if "(exp₁) op (exp2)" is a normal fully paren-
thesized expression whose operation is op, the postfix version of this is "pexp₁
pexp2 op", where pexp₁ is the postfix version of exp₁ and pexp2 is the postfix ver-
sion of exp2. The postfix version of a single number or variable is just that number
or variable. So, for example, the postfix version of "((5+2) * (8 − 3))/4" is "5
* 4 /". Describe a nonrecursive way of evaluating an expression in
postfix notation.
2+83-

P-6.35 Implement a program that can input an expression in postfix notation (see Exer-
cise C-6.19) and output its value.

Expert Solution

Step 1

6.15 )solution

def post_fix(expression):
    
    character = expression.split(" ")
    stack = []
    while len(character) > 0:
        item = character.pop(0)

        if item.isdigit():
            stack.append(int(item))
        elif item == "+":
            if len(stack) > 1:
                stack.append(stack.pop() + stack.pop())
            else:
                return "Invalid expression found"
                break

        elif item == "-":
            if len(stack) > 1:
                tmp = stack.pop()
                stack.append(stack.pop() - tmp)
            else:
                return "Invalid expression found"
                break

        elif item == "/":
            if len(stack) > 1:
                tmp = stack.pop()
                stack.append(stack.pop() / tmp)
            else:
                return "Invalid expression found"
                break
        elif item == "*":
            if len(stack) > 1:
                stack.append(stack.pop() * stack.pop())
            else:
                return "Invalid expression found"
                break

        elif item == "^":
            if len(stack) > 1:
                tmp = stack.pop()
                stack.append(pow(stack.pop(), tmp))
            else:
                return "Invalid expression found"
                break

        else:
            break
    
    return stack.pop()

print("Your postfix expression 3 4 5 + *  evaluates to : ",post_fix("3 4 5 + *"))
print("Your postfix expression 2 1 + 3 *  evaluates to : ",post_fix("2 1 + 3 *"))

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