Comparison operator

• ==
• ===
• !=
• !===
• >
• <
• >=
• <=

Logical operator

• &&
• ||
• !

Conditional Statement

var allan = "kekar";

if(allan == "kekar"){

    console.log("true block")

}

if(days >= 20){
    // I am just statement / block
    alert("sleep or die !");
}else{
    // I am a function
    goToWork();
}

if(age >= 20){
    console.log("adult");
}else if(age >= 5 && age >= 20){
    console.log("teen");
}else{
    console.log("baby");
}

switch(day){
  case 0:
    console.log("happy day");
    break;
  case 1:
    myBoringDay();
    break;
  default:
    alert("Hello World");
}

Looping

for(i = 0; i < 10; i++){
  alert("Alerting you 10 times");
}

for(i = 0; i < 10; i++){
  if(i % 3 == 0){
    alert("Multiplication of 3")
  }else{
    alert("Alerting you");  
  }
}

for(i = 0; i < 10; i++){
  console.log("i = "+i);
  for(j = 0; i < 5; i++){
    console.log("i inside another loop = "+i);
    console.log("j = "+j);
  } 
}

while(i < 99){
  console.log("increment using while => "+ i);
  i++;
}

i = 10
while(i > 0){
  console.log("increment using while => "+ i);
  i--;
}

do{
  console.log("loop using do while => "+i);
  i++;
}while(i < 10);

Data types

1. String
2. Number (Integer & Decimal)
3. Boolean
4. Object
5. Array

// to check type, use typeof followed by your parameter
typeof 123;

var name = "Helmy"
var age = 26;
var normal = true;
var favorites = ["Coffee", "Tea", "Milk"];
var helmy = {name: name, age: age, normal: normal, favorites: favorites};
console.log(name);
console.log(favorites[2]);
console.log(helmy.age);
console.log(helmy.favorites[0]);

Now please continue your calculator