#include <stdio.h>

int main (int argc, char *argv[]) {
    float first;
    float second;
    float result;
    int operator;
    
    printf("Enter first operand: "); 
    scanf("%f", &first);
    printf("/nEnter 1 for (+), 2 for (-), 3 for (*), 4 for (/): ");
    scanf("%d", &operator);
    if (operator == 4) {
        do {
            printf("/nEnter second operand: ");
            scanf("%f", &second);
        } while (second == 0);
    } else {
        printf("/nEnter second operand: ");
        scanf("%f", &second);
    }
    switch (operator) {
    case 1:
        result = first + second;
        break;
    case 2:
        result = first - second;
        break;
    case 3:
        result = first * second;
        break;
    case 4:
        result = first / second;
        break;
    default:
        printf("Unknown operator\n");
        return 1;
    }
    
    printf("Result is: %f \n", result);
    return 0;
}