main.c

gistfile1.txt

#include <stdio.h>
#include <stdlib.h>

int main(void) {
    int operand1, operand2;
    char operator;
    scanf("%d %c %d", &operand1, &operator, &operand2);

    int result = 0;
    char* print_out = NULL;
    switch (operator) {
        case '+':
            result = operand1 + operand2;
            break;
        case '-':
            result = operand1 - operand2;
            break;
        case '*':
            result = operand1 * operand2;
            break;
        case '/':
            result = operand1 / operand2;
            break;
        case '%':
            result = operand1 % operand2;
            break;
        default:
            print_out = "ERROR";
    }
    char str[sizeof(int) * 4];
    if (!print_out) {
        sprintf(str, "%d", result);
        print_out = str;
    }

    printf(print_out);
}