First and Last Occurrence of Element in DSA Javascript - Build from Scratch

First and Last Occurrence of Element

📖 Scenario: Imagine you have a list of daily temperatures recorded over a week. You want to find out on which days a specific temperature first and last appeared.

🎯 Goal: You will create a program that finds the first and last positions of a given temperature in the list.

📋 What You'll Learn

Create an array called temperatures with exact values: [23, 25, 23, 22, 25, 26, 23]

Create a variable called targetTemp and set it to 23

Write code to find the first and last occurrence indexes of targetTemp in temperatures

Print the first and last occurrence indexes in the format: First occurrence: X and Last occurrence: Y

💡 Why This Matters

🌍 Real World

Finding first and last occurrences helps in analyzing repeated events, like tracking when a temperature first and last appeared in weather data.

💼 Career

This skill is useful in data analysis, debugging logs, and searching through records efficiently.

1

Create the temperature list

Create an array called temperatures with these exact values: [23, 25, 23, 22, 25, 26, 23]

DSA Javascript

// Create the array temperatures with the given values
// Your code here

Hint

Use const temperatures = [23, 25, 23, 22, 25, 26, 23]; to create the array.

2

Set the target temperature

Create a variable called targetTemp and set it to 23

DSA Javascript

const temperatures = [23, 25, 23, 22, 25, 26, 23];
// Create the variable targetTemp and set it to 23
// Your code here

Hint

Use const targetTemp = 23; to set the target temperature.

3

Find first and last occurrence indexes

Create two variables called firstIndex and lastIndex. Use temperatures.indexOf(targetTemp) to find the first occurrence and temperatures.lastIndexOf(targetTemp) to find the last occurrence.

DSA Javascript

const temperatures = [23, 25, 23, 22, 25, 26, 23];
const targetTemp = 23;
// Find firstIndex and lastIndex of targetTemp in temperatures
// Your code here

Hint

Use indexOf and lastIndexOf methods on the array.

4

Print the results

Print the first occurrence index with console.log("First occurrence: " + firstIndex) and the last occurrence index with console.log("Last occurrence: " + lastIndex).

DSA Javascript

const temperatures = [23, 25, 23, 22, 25, 26, 23];
const targetTemp = 23;
const firstIndex = temperatures.indexOf(targetTemp);
const lastIndex = temperatures.lastIndexOf(targetTemp);
// Print the first and last occurrence indexes
// Your code here

Hint

Use console.log to print the results exactly as shown.