Lists Lesson 
%%js 

// Popcorn Hack 1: Initialize Snake
// ===============================
// TODO: Make an array called snake with:
//  - 1 head ("H")
//  - 3 body segments ("B")
//  - 1 tail ("T")
// Hint: arrays in JavaScript use [ ... ] with commas.

let snake = ["H", "B", "B", "B", "T"];  // <-- fill this in

console.log("Starting snake:", snake);


// ===============================
// Popcorn Hack 2: Growing the Snake
// ===============================
//  - Add 2 tails ("T") to the END of the array
//  - Use push() twice
// Example: snake.push("T")

// Your code here

snake.push("T");
snake.push("T");

console.log("Snake after eating:", snake);


// ===============================
// Popcorn Hack 3: Snake Loses a Tail
// ===============================
// TODO: The snake moves forward, tail disappears
//  - Remove the LAST 2 elements
//  - Use pop() twice
// Example: snake.pop()

// Your code here

snake.pop();
snake.pop();

console.log("Snake after losing tails:", snake);


// ===============================
// Popcorn Hack 4: Combining It All
// ===============================
// TODO:
//  Step 1: Add 2 new heads ("H") to the START of the array
//  Step 2: Remove 1 head from the START of the array
//  Step 3: Print the new snake and its first head

// Your code here

snake.unshift("H");
snake.unshift("H");

snake.shift();

console.log("Snake after moving:", snake);
console.log("New first head is:", snake[0]);


// ===============================
// Check Your Understanding
// ===============================
// Start fresh with a new snake


// Your code here

snake = ["H", "B", "B", "T"];

snake.unshift("H");

snake.push("T");

snake.splice(2, 1);

console.log("Final snake:", snake);
console.log("First head:", snake[0]);
console.log("Last element:", snake[snake.length - 1]);


<IPython.core.display.Javascript object>