#include <cstring>
#include <iostream>
using namespace std;
 
int main()
{
    setlocale(LC_CTYPE, "rus");
    cout << "Введите строку: ";
    char arr[100], num[10], znak = '+';
    int summa = 0;
    cin.getline(arr, 100);
    for (int i = 0, j = 0; i < strlen(arr); i++)
    {
        if (strchr("+-", arr[i]))
        {
            if (znak == '+')
                summa += atoi(num);
            else
                summa -= atoi(num);
            j = 0;
            num[0] = '\0';
            znak = arr[i];
        }
        else
        {
            num[j++] = arr[i];
            num[j] = '\0';
        }
    }
    if (znak == '+') 
        summa += atoi(num);
    else 
        summa -= atoi(num);
    cout << arr << " = " << summa << endl;
    system("pause");
    return 0;
}