infix to postfix conversion using stack in c++ code example

Example 1: infix to postfix program in c++

/*https://github.com/Sudhanshu1304/Stack-Application*/

#include 
#include
using namespace std;



class Stack{


private:


    char A[5];
    int Size;

public:
    int top;
    Stack(){

        top=-1;
        Size=sizeof(A)/sizeof(char);

    }



    bool IsFull(){

        if(top==Size-1){
            return true;
        }
        else{
            return false;
        }
    }

    bool IsEmpty(){

        if(top==-1){
            return true;
        }
        else{
            return false;
        }
    }

    char peek(){

        return A[top];
    }

    void Push(char val){

        if (IsFull()==false){
            top++;
            A[top]=val;
        }
        else{
            cout<<"\nThe Stack is Full"<=6){
                    return i+i;
                }
                else{
                    return i+i+0;
                }

        }
        else if(CHAR[i][1]==A){
             if(i+i>=6){
                    return i+i;
                }
                else{
                    return i+i+1;
                }
        }
    }
    return -1;

}




void Display(char ch,string vari, Stack &s){

    int Size=s.top+1;


    cout<<"\n   "<>exp;

    string out="";
    cout<<"\n\nExpression   Stack   Postfix\n"<=3){



                while(Search(STACK.peek())>2){
                    char val=STACK.Pop();
                        out=out+val;

                    Display(temp,out,STACK);
                }
                STACK.Pop();
                Display(temp,out,STACK);
                }
            /* Search Precedence*/
            else{
                if (Search(temp)>=0 && Search(temp)<=2){
                    STACK.Push(temp);
                    Display(temp,out,STACK);
                }

                /* If TOP < Temp */

                else if(Search(STACK.peek())=ab){

                        char val=STACK.Pop();
                            out=out+val;
                        Display(temp,out,STACK);
                    }
                    STACK.Push(temp);
                    Display(temp,out,STACK);
                }
            }
        }
        /* If an Alphabet */
        else{

            out=out+temp;
            Display(temp,out,STACK);

            }


    }
    while(STACK.IsEmpty()==false){

        char val=STACK.Pop();

            out=out+val;
        Display(temp,out,STACK);

    }
    cout<<"\n\nFINAL STRING : "<

Example 2: python postfix conversion

"""
Author : ITVoyagers (itvoyagers.in)

Date :31st October 2019

Description : Program to show use of stack in infix to postfix conversion using python.
"""
class infix_to_postfix:
    precedence={'^':5,'*':4,'/':4,'+':3,'-':3,'(':2,')':1}
    def __init__(self):
        self.items=[]
        self.size=-1
    def push(self,value):
        self.items.append(value)
        self.size+=1
    def pop(self):
        if self.isempty():
            return 0
        else:
            self.size-=1
            return self.items.pop()
    def isempty(self):
        if(self.size==-1):
            return True
        else:
            return False
    def seek(self):
        if self.isempty():
            return false
        else:
            return self.items[self.size]
    def isOperand(self,i):
        if i in 'ABCDEFGHIJKLMNOPQRSTUVWXYZ':
            return True
        else:
            return False
    def infixtopostfix (self,expr):
        postfix=""
        print('postfix expression after every iteration is:')
        for i in expr:
            if(len(expr)%2==0):
                print("Incorrect infix expr")
                return False
            elif(self.isOperand(i)):
                postfix +=i
            elif(i in '+-*/^'):
                while(len(self.items)and self.precedence[i]<=self.precedence[self.seek()]):
                    postfix+=self.pop()
                self.push(i)
            elif i is '(':
                self.push(i)
            elif i is ')':
                o=self.pop()
                while o!='(':
                    postfix +=o
                    o=self.pop()
            print(postfix)
                #end of for
        while len(self.items):
            if(self.seek()=='('):
                self.pop()
            else:
                postfix+=self.pop()
        return postfix
s=infix_to_postfix()
expr=input('enter the expression ')
result=s.infixtopostfix(expr)
if (result!=False):
    print("the postfix expr of :",expr,"is",result)

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