#include <stdio.h>
int main()
{

    FILE *fp_read, *fp_write;
    char operation;
    float op1, op2, res;

    if ((fp_read = fopen("./Operations.txt", "r")) == NULL)
    {
        printf("Error opening file\n");
        return 1;
    }
    if ((fp_write = fopen("./Results.txt", "w")) == NULL)
    {
        printf("Error opening file\n");
        return 2;
    }

    while (!feof(fp_read))
    {
        fscanf(fp_read, " %c %f %f", &operation, &op1, &op2);
        if (!feof(fp_read))
        {
            switch (operation)
            {
            case '+':
                res = op1 + op2;
                break;

            case '-':
                res = op1 - op2;
                break;

            case '*':
                res = op1 * op2;
                break;

            case '/':
                if (op2 == 0)
                {
                    printf("Error: divide by zero\n");
                    return 3;
                }
                res = op1 / op2;
                break;

            default:
                printf("Error: invalid operation\n");
                return 1;
            }

            fprintf(fp_write, "%c %.2f\n", operation, res);
        }
    }

    fclose(fp_read);
    fclose(fp_write);

    return 0;
}