How can I extract a specific element from an array by inputting its index position?

I am attempting to find out which teacher is responsible for a particular student based on the classroom they are in. Each teacher corresponds to a specific set of classrooms.

let teachers = ["Arrington", "Kincart", "Alberts", "Pickett"]

let rooms = [
  ["Andy", "Rodolfo", "Lynn", "Talia"],
  ["Al", "Ross", "Jorge", "Dante"],
  ["Nick", "Kim", "Jasmine", "Dorothy"],
  ["Adam", "Grayson", "Aliyah", "Alexa"]
]

let findTeacher = (student) => {
    return rooms.findIndex(row => row.indexOf(student) !== -1)
}

console.log(`The teacher who manages Jorge is ${findTeacher("Jorge")}.`)
console.log(`The teacher who guides Alexa is ${findTeacher("Alexa")}.`)

The current result shows:

The teacher who has Jorge is 1.
The teacher who has Alexa is 3.

I realize that I'm close, but I need assistance in outputting the actual name of the teacher instead of just their index number.

javascriptarraysmultidimensional-array

Answer №1

Utilize the array of teachers that you have forgotten to include. By utilizing indexing, you can successfully achieve your desired outcome:

let teachers = ["Smith", "Johnson", "Williams", "Jones"]


let classes = [
  ["Emma", "Liam", "Olivia", "Noah"],
  ["Ava", "Isabella", "James", "Sophia"],
  ["Logan", "Lucas", "Mia", "Ethan"],
  ["Amelia", "Michael", "Charlotte", "Daniel"]
]

let findTeacher = (student) => {
    return teachers[classes.findIndex(row => row.indexOf(student) !== - 1)]
    //             ^ use the located index to reference the teachers array
}


console.log(`The teacher of James is ${findTeacher("James")}.`)
console.log(`The teacher of Amelia is ${findTeacher("Amelia")}.`)

Answer №2

If you need to find the teacher corresponding to a student, you can simply access the teacher at the specified index within the teachers array:

const teachers = ["Arrington", "Kincart", "Alberts", "Pickett"]
const rooms = [
  ["Andy", "Rodolfo", "Lynn", "Talia"],
  ["Al", "Ross", "Jorge", "Dante"],
  ["Nick", "Kim", "Jasmine", "Dorothy"],
  ["Adam", "Grayson", "Aliyah", "Alexa"]
]
const findTeacher = student => teachers[ rooms.findIndex(row => row.includes(student)) ]


console.log(`The teacher of Jorge is ${ findTeacher("Jorge") }.`)
console.log(`The teacher of Alexa is ${ findTeacher("Alexa") }.`)

(By the way: it's recommended to use const over let, especially for arrow functions, and utilize built-in functions like Array.prototype.includes for improved clarity and potentially better performance.)

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