Reverse the infix string. Note that while reversing the string you must interchange left and right parentheses

Last update: Jan 04, 2022

Overview

Infix-to-Prefix-Convertion-by-Python

def isOperator(c): return (not (c >= 'a' and c <= 'z') and not(c >= '0' and c <= '9') and not(c >= 'A' and c <= 'Z'))

def getPriority(C): if (C == '-' or C == '+'): return 1 elif (C == '*' or C == '/'): return 2 elif (C == '^'): return 3 return 0

def infixToPrefix(infix): operators = [] operands = []

for i in range(len(infix)):
    
    if (infix[i] == '(' ):
        operators.append(infix[i])

    elif (infix[i] == ')'):
        while (len(operators)!=0 and (operators[-1] != '(' )):
            op1 = operands[-1]
            operands.pop()
            op2 = operands[-1]
            operands.pop()
            op = operators[-1]
            operators.pop()
            tmp = op + op2 + op1
            operands.append(tmp)
        operators.pop()
    elif (not isOperator(infix[i])):
        operands.append(infix[i] + "")

    else:
        while (len(operators)!=0 and getPriority(infix[i]) <= getPriority(operators[-1])):
            op1 = operands[-1]
            operands.pop()

            op2 = operands[-1]
            operands.pop()

            op = operators[-1]
            operators.pop()

            tmp = op + op2 + op1
            operands.append(tmp)
        operators.append(infix[i])

while (len(operators)!=0):
    op1 = operands[-1]
    operands.pop()

    op2 = operands[-1]
    operands.pop()

    op = operators[-1]
    operators.pop()

    tmp = op + op2 + op1
    operands.append(tmp)
return operands[-1]

while(1): s = input("Infix Expression : ") print("Prefix Expression : ", infixToPrefix(s))

Step 1: Reverse the infix string. Note that while reversing the string you must interchange left and right parentheses. Step 2: Obtain the postfix expression of the infix expression Step 1. Step 3: Reverse the postfix expression to get the prefix expression

Reverse the infix string. Note that while reversing the string you must interchange left and right parentheses

Related tags

Overview

Infix-to-Prefix-Convertion-by-Python

Owner

Sazzad Hossen

A Github Action for sending messages to a Matrix Room.

A desktop app to check the unlocked courses bases on previously done courses.

Repo contains Python Code Reference to learn Python in a week, It also contains Machine Learning Algorithms and some examples for Practice, Also contains MySql, Tableau etc

The only purpose of a byte-sized application is to help you create .desktop entry files for downloaded applications.

This is a calculator of strike price distance for options.

NCAR/UCAR virtual Python Tutorial Seminar Series lesson on MetPy.

pyForgeCert is a Python equivalent of the original ForgeCert written in C#.

This repo created to complete the task HACKTOBER 2021, contribute now and get your special T-Shirt & Sticker. TO SUPPORT OWNER PLEASE PRESS STAR BUTTON

Este script añade la config de s4vitar a bspwm automaticamente!

Python plugin/extra to load data files from an external source (such as AWS S3) to a local directory

resultados (data) de elecciones 2021 y código para extraer data de la ONPE

This bot uploads telegram files to MixDrop.co,File.io.

A collection of software that serve no purpose other than waste your time. Forking is encouraged!

This is the key combo trainer for League of Legends and Dota 2 players.

WriteAIr is a website which allows users to stream their writing.

Control your gtps with gtps-tools!

Imitate Moulinette written in Python

Creates infinite amount of guilded accounts in seconds.

Python Osmium Examples

Blender Light Manipulation - A script that makes it easier to work with light