infix to postfix conversion

[hamzamughal]

It does not show any output.

 #include <iostream>
#include <conio.h>
#include <string.h>
#include <sstream>
									
					/*C++ code to convert infix expression to postfix exprssion .*/
						
using namespace std;

//node class
class node{
    
    private:
    	char object;
		node *nextNode;
	
	public:
	
		char get() {
			
			return object;
		}
	
		void set(char object) {
			
			this->object = object;
		}	
	
		node *getNext() {
			
			return nextNode;
		}
	
		void setNext(node *nextNode) {
			
			this->nextNode = nextNode;			
		}
};node *headNode = NULL, *currentNode = NULL, *lastcurrentNode = NULL, *pointer; //objects of node class
//node class end

class stack{//stack class start
	
	private:
		int size;
		
	public:
		
		stack(){
			size=0;
		}
		
		void push(char x){ //push function of Stack //which pushes the values 
	    	
			headNode = new node;
	    	headNode-> set(x);
	    	headNode->setNext(NULL);
	    	
			if ( lastcurrentNode == NULL ) {	//this conditions checks if single node is created
	        	lastcurrentNode = headNode;
	    }
			
			else { //this conditions checks if more than one node is created
	     
		    	currentNode = lastcurrentNode; 
	        	lastcurrentNode = headNode;
	        	headNode->setNext(currentNode);
	    }
	    size++;
	}
	
		char pop() { //pop function of stack class //which pop up the values
	    	
			if (lastcurrentNode == NULL) {
	        	cout<<"Stack is Empty";
	    }
			else {
	        	pointer = lastcurrentNode;
	        	lastcurrentNode = lastcurrentNode->getNext();
	        	return(pointer->get());
	        	delete pointer;
	    }
	    size--;
	}
	
		char top(){
		
			return headNode->get();
		
		}
		
		char empty(){
			
			return (headNode==NULL);
		}
};
//stack class ends

int priority(char x){
	
	int temp;
	if(x == '*' || x == '/'){
		temp = 1;
	}
	if(x == '+' || x == '-'){
		temp = 2;
	}
	return temp;
}

/*void converter(char infix[], char postfix[], int size){
	
	stack obj;
	int prio;
	int i=0;
	int k=0;
	char itrever;
	
	//itrever the infix expression
	while(i<size){
		itrever = infix[i];
		if(itrever == '('){
			obj.push(itrever);
			i++;
			continue;
		}
		if(itrever == ')'){
			while(!obj.empty() && obj.top() != '('){
				postfix[k++]=obj.top();
				obj.pop();
			}
			if(!obj.empty()){
				obj.pop();
			}
			i++;
			continue;
		}
		prio = priority(itrever);
			if(prio == 0){
				postfix[k++] = itrever;
			}
			else{
				if(obj.empty()){
					obj.push(itrever);
				}
				else{
					while(!obj.empty() && obj.top() != '(' && prio<=priority(obj.top())){
						postfix[k++] = obj.top();
						obj.pop();
					}
					obj.push(itrever);
				}
			}
			i++;
		}
		
	
	while(!obj.empty()){
		postfix[k++] = obj.top();
		obj.pop();
	}
	postfix[k] = 0;
} */

	
//main
int main() {
    
	char infix[] = "A*(B+C)";
	/*int size = strlen(infix);
	char postfix[size];
	converter(infix,postfix,size);
	cout<<"\nInfix Expression: "<<infix;
	cout<<"\nPostfix Expression: "<<postfix;*/
	
	stack obj;
	int size = strlen(infix);
	stringstream output;
	for(int i=0; i<size; i++){
		if(infix[i] == '+' || infix[i] == '-' || infix[i] == '*' || infix[i] == '/'){
			while(!obj.empty() && priority(obj.top()) <= priority(infix[i])){
				output<<obj.top();
			}
			obj.push(infix[i]);
		} 
		else if(infix[i] == '('){
			obj.push(infix[i]);
		}
		else if(infix[i] == ')'){
			while(obj.top() != '('){
				output<<obj.top();
				obj.pop();
			}
			obj.pop();
		} 
		else{
			output<<infix[i];
		}	
	}
	while(!obj.empty()){
		output<<obj.top();
		obj.pop();
	}
	cout<<output.str();
    getch();
}
	
													/*    Program End     */