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

int main(int argc, char *argv[]) {
  // Check if the user has provided exactly three arguments
  if (argc != 3) {
    printf("Usage: calculator <operator> <number1> <number2>\n");
    return 1;
  }

  // Convert the operator and numbers to doubles
  double operator = atof(argv[1]);
  double number1 = atof(argv[2]);
  double number2 = atof(argv[3]);

  // Perform the calculation based on the operator
  double result;
  switch (operator) {
    case '+':
      result = number1 + number2;
      break;
    case '-':
      result = number1 - number2;
      break;
    case '*':
      result = number1 * number2;
      break;
    case '/':
      result = number1 / number2;
      break;
    default:
      printf("Unsupported operator: %s\n", argv[1]);
      return 1;
  }

  // Print the result
  printf("%f\n", result);

  return 0;
}

gcc -o calculator calculator.c
./calculator <operator> <number1> <number2>

./calculator + 10 20

30.000000