Calculator using if else

const prompt = require("prompt-sync")();

let operator = prompt("Enter the operator (+, -, *, /) :");
let n1 = prompt("Enter the number : ");
n1 = parseInt(n1);
let n2 = prompt("Enter the number : ");
n2 = parseInt(n2);
let res;

if (operator == "+") {
  res = n1 + n2;
} else if (operator == "-") {
  res = n1 - n2;
} else if (operator == "*") {
  res = n1 * n2;
} else {
  res = n1 / n2;
}
console.log(`${n1} ${operator} ${n2} = ${res}`);