중위표기식을 후위표기식으로 변환

#include <stdio.h>
#include <stack>
#include <iostream>
#include <conio.h>
 
/*
#include <iostream>
#include <assert.h>
#include <errno.h>
#include <setjmp.h>
#include <stdarg.h>
#include <algorithm>
*/
 
#include <queue>
#include <deque>
#include <vector>
 
/* run this program using the console pauser or add your own getch, system("pause") or input loop */
 
using namespace std;
 
//typedef stack<int, deque<int> > STACK_INT;
 
//https://support.microsoft.com/ko-kr/kb/158040
stack<char> s;
//deque<char> s;
 
//[Error] 'getche' was not declared in this scope
//http://kcoder.tistory.com/43
 
char print[99999];
int i=0;
 
int cnt=0;
 
int precedence(int op)
{
printf("0 %d\n", cnt); cnt++;
    if (op == '(')
    {
printf("1 %d\n", cnt); cnt++;
        return 3;
    }
    if (op == '+' || op == '-')
    {
printf("2 %d\n", cnt); cnt++;
        return 1;
    }
    if (op == '*' || op == '/')
    {
printf("3 %d\n", cnt); cnt++;
        return 2;
    }
    else
    {
printf("4 %d\n", cnt); cnt++;
        return 0;
    }
}
 
int cal(char a)
{
printf("5x %d\n", cnt); cnt++;
    if(a=='(')
    {
printf("5 %d\n", cnt); cnt++;
        s.push('(');
printf("6 %d\n", cnt); cnt++;
    }
    else if(a==')')
    {
printf("7x %d\n", cnt); cnt++;
        while(s.top()!='(')
        {
printf("7 %d\n", cnt); cnt++;
            print[i]=s.top();
printf("8 %d\n", cnt); cnt++;
            i++;
printf("9 %d\n", cnt); cnt++;
            s.pop();
printf("10 %d\n", cnt); cnt++;
        }
printf("11 %d\n", cnt); cnt++;
        s.pop();
printf("12 %d\n", cnt); cnt++;
    }
    else if(a=='+'||a=='-'||a=='*'||a=='/')
    {
printf("13x %d\n", cnt); cnt++;
        while(precedence(s.top())>=precedence(a))   //여기서 문제 발생 
        {
printf("13 %d\n", cnt); cnt++;
            print[i]=s.top();
printf("14 %d\n", cnt); cnt++;
            i++;
printf("15 %d\n", cnt); cnt++;
            s.pop();
printf("16 %d\n", cnt); cnt++;
            s.push(a);
printf("17 %d\n", cnt); cnt++;
        }
printf("17x %d\n", cnt); cnt++;
    }
    else
    {
printf("18 %d\n", cnt); cnt++;
        print[i]=a;
printf("19 %d\n", cnt); cnt++;
        i++;
printf("20 %d\n", cnt); cnt++;
    }
printf("20x %d\n", cnt); cnt++;
}
 
 
 
int main(int argc, char** argv)
{
    char a;
    int j;
    for(;a=')';)
    {
printf("21 %d\n", cnt); cnt++;
        a=getch();
printf("22 %c\n",a);
printf("23 %d\n", cnt); cnt++;
        cal(a);
printf("24 %d\n", cnt); cnt++;
    }
printf("end\n");
 
    while(!s.empty())
    {
printf("25 %d\n", cnt); cnt++;
        print[i]=s.top();
printf("26 %d\n", cnt); cnt++;
        s.pop();
printf("27 %d\n", cnt); cnt++;
    }
    for(i=j;j<=i;j++)
    {
printf("28 %d\n", cnt); cnt++;
        printf("%c",print[j]);
printf("29 %d\n", cnt); cnt++;
    }
    return(0);
}
 
 
 
#if 0
21 0
22 +
23 1
5x 2
13x 3
#endif