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# Bare Python terminal script — wrong platform entirely
def calculator():
    a  = float(input("Enter first number: "))
    op = input("Enter operator (+, -, *, /): ")
    b  = float(input("Enter second number: "))
    if op == "+": print(a + b)
    elif op == "-": print(a - b)
calculator()

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// Ask the user for their name
const name = prompt("What is your name?");
// Opens a browser dialog. Whatever the user types → stored in `name`.

// Ask the user for their favorite color
const color = prompt("What is your favorite color?");
// Same pattern. Result stored in `color`.

// Create a greeting message using the inputs
const message = "Hello, " + name + "! Your favorite color is " + color + ".";
// + glues four string pieces into one sentence.

// Display the message on the page
document.write(message);
// Writes the string directly into the HTML page body.

const name  = prompt("What is your name?");
const color = prompt("What is your favorite color?");
const food  = prompt("What is your favorite food?");  // ← NEW

const message =
  "Hello, " + name +
  "! Your favorite color is " + color +
  " and your favorite food is " + food + ".";  // ← UPDATED

document.write(message);

Line	Concept	Key takeaway
const name = prompt(...)	const, prompt()	Stores user input as a string
const color = prompt(...)	Same pattern	Each prompt() is its own dialog
const message = ... + ...	Concatenation	+ joins strings; order matters
document.write(message)	DOM output	Dumps text straight onto the page
Cancel button	null	Always guard real apps against null input

// Get the bill amount from the user
const bill = parseFloat(prompt("Enter the bill amount:"));

// Get the tip percentage
const tipPercent = parseFloat(prompt("Enter tip percentage (e.g., 20 for 20%):"));

// Calculate the tip
const tip = bill * (tipPercent / 100);

// Calculate the total
const total = bill + tip;

// Display the results
document.write("<h2>Tip Calculator</h2>");
document.write("<p>Bill: $" + bill.toFixed(2) + "</p>");
document.write("<p>Tip (" + tipPercent + "%): $" + tip.toFixed(2) + "</p>");
document.write("<p>Total: $" + total.toFixed(2) + "</p>");

Line	Variable	Value
const bill = ...	bill	50
const tipPercent = ...	tipPercent	20
const tip = ...	tip	10.00  (50 × 0.20)
const total = ...	total	60.00  (50 + 10)

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Step	Calculation	Result
Input (F)	212	212
F − 32	212 − 32	180
× 5/9	180 × 5/9	100°C

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