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#include <cstdio>
#include <stack>
#include <map>
using namespace std;
int current_number = 0;
void process_a_digit(char ch) {
    current_number = current_number * 10 + (ch - '0');
}
map<char, int> precedence;
stack<int> number_stack;
stack<char> operator_stack;
void calculate_a_num() {
    int num2 = number_stack.top(); number_stack.pop();
    int num1 = number_stack.top(); number_stack.pop();
    char op = operator_stack.top(); operator_stack.pop();
    int num = 0;
    switch (op) {
    case '+':num = num1 + num2; break;
    case '-':num = num1 - num2; break;
    case '*':num = num1 * num2; break;
    case '/':num = num1 / num2; break;
    }
    number_stack.push(num);
}
int get_precedence(char op1, char op2) {
    if (op1 == '(' || op2 == '(') {
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