Infix to Postfix conversion

//A C++ program to convert an infix expression to postfix expression by Abhi Agarwal
 #include<iostream.h>
#include<conio.h>
#include<string.h>
#include<process.h>
char  infix[50];  //It will store the infix expression the user enters
char stack[100]; //For storing intermediate results
char exp[50];    //It will store the postfix expression.
int top_stack,top_exp; //top_stack holds the index of the top of the stack[] and  //top_exp holds the index of the top of exp[].
void accept()
{
    int i;
    cout<<"Expression can contain +,-,/,%,*,()";
    cout<<"Enter the infix expression...";
    cin>>infix;
    i=strlen(infix);
    *(infix+i)='#';
    cout<<infix;
}
int precedence(char s)//function to find the precedence of operators
{
     switch(s)
     {
          case '+':
                return 2;
          case '-':
                return 2;
          case '*':
                return 1;
          case '/':
                return 1;
          case '%':
                return 1;
          default:
                return 0;
      }
}
void postfix()
{
   int i=0,n,k;
   top_stack++;
   *(stack+top_stack)='(';
   while(1)
   {
        if(*(infix+i)=='(')
       {
            top_stack++;
            *(stack+top_stack)='(';
       }
       else if(*(infix+i)=='+'||*(infix+i)=='-'||*(infix+i)=='/'||*(infix+i)=='*'||*(infix+i)=='%')
       {
             n=precedence(*(infix+i));
             k=precedence(*(stack+top_stack));
             if(k<n)
            {
                  top_stack++;
                  *(stack+top_stack)=*(infix+i);
            }
            else
           {
                  while(n<k)
                  {
                          top_exp++;
                          *(exp+top_exp)=*(stack+top_stack);
                          top_stack--;
                          k=precedence(*(stack+top_stack));
                  }
                  if(n==k||n>k)
                  {
                           top_stack++;
                           *(stack+top_stack)=*(infix+i);
                   }
              }
    }
         else if(*(infix+i)==')')
         {
                   while(*(stack+top_stack)!='(')
                   {
                              top_exp++;
                              *(exp+top_exp)=*(stack+top_stack);
                              top_stack--;
                    }
                   top_stack--;
         }
         else if(*(infix+i)=='#')
         {
                   while(*(stack+top_stack)!='(')
                    {
                                top_exp++;
                                *(exp+top_exp)=*(stack+top_stack);
                                top_stack--;
                     }
                    break;
         }
         else
         {
                     top_exp++;
                     *(exp+top_exp)=*(infix+i);
         }
          i++;
   }
}
void display()
{
    cout<<"Postfix expresion is....\n";
    cout<<exp;
}
void main()
{
    clrscr();//used to clear the screen
    top_stack=-1;
    top_exp=-1;
    accept();//function call to accept the infix expression
    postfix();//function to convert the infix into postfix expression
    display();//display the postfix expression
    getch();//function to hold the output screen
}