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#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <malloc.h>
#include <stdbool.h>
#include <string.h>
#include <ctype.h>
char postfix_str[1001] = { 0 }; //the reason why i lost 2 weeks
//stack_begin

struct list
{
    char data;
    struct list * next;
};
typedef struct stack
{
    struct list *top;
} stack;

stack *construct()
{
    stack *_stack;
    _stack = (stack*)malloc(sizeof(stack));
    _stack->top = NULL;
    return _stack;
}

void push(stack *_stack, int a)
{
    struct list *p;
    p = (struct list *) malloc(sizeof(struct list));
    p->data = a;
    p->next = _stack->top;
    _stack->top = p;
}

char top(stack *_stack)
{
    return (_stack->top->data);
}

int is_empty(stack *_stack)
{
    if (_stack->top == NULL)
        return 1;
    return 0;
}

char pop(stack *_stack)
{
    char a;
    struct list *p;
    p = _stack->top;
    a = p->data;
    _stack->top = p->next;
    free(p);
    return a;
}

//stack_end

int get_priority(char symbol)
{
    char operations[] = "()+-*/";
    for (size_t priority = 0; operations[priority] != '\0'; priority++)
    {
        if (symbol == operations[priority])
            return priority / 2;
    }
    return -1;
}


char *to_postfix(char infix_str[])
{
    int priority = 0;
    stack *postfix_stack = construct();
    int j = 0;
    for (int i = 0; infix_str[i] != '\0'; i++)
    {
        priority = get_priority(infix_str[i]);
        if (priority == -1)
        {
            postfix_str[j++] = infix_str[i];
            continue;
        }
        if (infix_str[i] == '(')
        {
            push(postfix_stack, infix_str[i]);
            continue;
        }
        if (infix_str[i] == ')')
        {
            while (top(postfix_stack) != '(')
            {
                postfix_str[j++] = pop(postfix_stack);
            }
            pop(postfix_stack);
            continue;
        }
        while (is_empty(postfix_stack) == 0 && priority <= get_priority(top(postfix_stack)))
        {
            postfix_str[j++] = pop(postfix_stack);
        }
        push(postfix_stack, infix_str[i]);
    }
    while (is_empty(postfix_stack) == 0)
    {
        postfix_str[j++] = pop(postfix_stack);
    }
    free(postfix_stack);
    return postfix_str;
}


int main()
{
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
    char in_str[1001] = { 0 };
    gets_s(in_str, 1001);
    printf("%s", to_postfix(in_str));
    return 0;
}