Loop through the array and print out only the last item

Question

Loop through the array and print out only the last item

I am struggling to get my for loop to print out every item in the array, instead of just the last item. Can't seem to figure out where I'm going wrong:

var patients = ["Julia", "Kelly", "Thomas", "Clare"];

function lineOfPatients(line) {
 if (!line.length) {
     return "Empty"
 }
 var list = "";
 for(var i = 0; i < line.length; i++) {
     list += `${i + 1}. ${line[i]}, `
 }
 return `The line is currently: ${list}`
}

lineOfPatients(patients)

This code snippet returns "The line is currently: 4. Clare,"

My desired output should be "The line is currently: 1. Julia, 2. Kelly, 3. Thomas, 4. Clare"

javascript arrays for-loop

Answer 1

Answer №1

If you have an array called patients, you can create a function in JavaScript to display the line of patients using the join method.

var patients = ["Julia", "Kelly", "Thomas", "Clare"];

function displayPatientLine(line) {
    if (!line.length) {
        return "No patients in line";
    }

    var lines = [];

    for(var i = 0; i < line.length; i++) {
        var patientName = `${i + 1}. ${line[i]}`
        lines.push(patientName)
    }

    return `The current line of patients is: ${lines.join(", ")}`;
}

console.log(displayPatientLine(patients));

Answer 2

If you have an array called patients, you can create a function in JavaScript to display the line of patients using the join method.

var patients = ["Julia", "Kelly", "Thomas", "Clare"];

function displayPatientLine(line) {
    if (!line.length) {
        return "No patients in line";
    }

    var lines = [];

    for(var i = 0; i < line.length; i++) {
        var patientName = `${i + 1}. ${line[i]}`
        lines.push(patientName)
    }

    return `The current line of patients is: ${lines.join(", ")}`;
}

console.log(displayPatientLine(patients));

Answer 3

Answer №2

The issue you're facing is the constant reassignment of the variable list within the loop, causing each iteration to overwrite the previous value.

To prevent this from happening, consider using the += operator instead of the = operator as shown below:

var patients = ["Alex", "Brianna", "Daniel", "Emma"];

function displayPatients(pList) {
 if (!pList.length) {
     return "The list is empty."
 }
 var queue = "";
 for(var j = 0; j < pList.length; j++) {
     queue += `${j + 1}. ${pList[j]}, `
 }
  return `Current patient lineup: ${queue}`
}

console.log(displayPatients(patients))

Answer 4

The issue you're facing is the constant reassignment of the variable list within the loop, causing each iteration to overwrite the previous value.

To prevent this from happening, consider using the += operator instead of the = operator as shown below:

var patients = ["Alex", "Brianna", "Daniel", "Emma"];

function displayPatients(pList) {
 if (!pList.length) {
     return "The list is empty."
 }
 var queue = "";
 for(var j = 0; j < pList.length; j++) {
     queue += `${j + 1}. ${pList[j]}, `
 }
  return `Current patient lineup: ${queue}`
}

console.log(displayPatients(patients))

Answer 5

Answer №3

Your code is facing an issue where each time your for-loop iterates, it reinitializes the variable list = `${i + 1}. ${line[i]},`. This results in list only containing the last element from the array when you finally return.

An alternative approach could be:

function displayPatientLine(line) {
  if (!line.length) {
    return "Empty"
  }
  var resultString = "The current line of patients: "
  for(let i = 0; i < line.length; i++) {
    let patient = ` ${i + 1}. ${line[i]},`;
    resultString += patient;
  }
  return resultString;
}

Answer 6

Your code is facing an issue where each time your for-loop iterates, it reinitializes the variable list = `${i + 1}. ${line[i]},`. This results in list only containing the last element from the array when you finally return.

An alternative approach could be:

function displayPatientLine(line) {
  if (!line.length) {
    return "Empty"
  }
  var resultString = "The current line of patients: "
  for(let i = 0; i < line.length; i++) {
    let patient = ` ${i + 1}. ${line[i]},`;
    resultString += patient;
  }
  return resultString;
}

Answer 7

Answer №4

Here is the solution you are looking for. (Got a bit carried away trying to make the code concise)

const patients = ["Julia", "Kelly", "Thomas", "Clare"]

const lineOfPatients = (line) => "The line currently consists of: " + (!line || !line.length) ? "Empty" : line.map((patient, idx) => `${idx + 1}. ${patient}`).join(', ')

console.log(lineOfPatients(patients))

The issue causing it not to work is that you are redefining the variable list inside every loop iteration. Even if you move it outside the loop, you are overwriting the output rather than appending to it within the for-loop. The final result will always be from the last iteration.

Answer 8

Here is the solution you are looking for. (Got a bit carried away trying to make the code concise)

const patients = ["Julia", "Kelly", "Thomas", "Clare"]

const lineOfPatients = (line) => "The line currently consists of: " + (!line || !line.length) ? "Empty" : line.map((patient, idx) => `${idx + 1}. ${patient}`).join(', ')

console.log(lineOfPatients(patients))

The issue causing it not to work is that you are redefining the variable list inside every loop iteration. Even if you move it outside the loop, you are overwriting the output rather than appending to it within the for-loop. The final result will always be from the last iteration.

Answer 9

Answer №5

In order to optimize your code, it is recommended that you declare the variable list outside of the loop so that it is not recreated with a new value on each iteration. You can do this by initializing it as an array before the loop like this:

var list = new Array();

Then, within your loop, you can add elements to the array without recreating it every time like so:

list[i] = .....

Answer 10

In order to optimize your code, it is recommended that you declare the variable list outside of the loop so that it is not recreated with a new value on each iteration. You can do this by initializing it as an array before the loop like this:

var list = new Array();

Then, within your loop, you can add elements to the array without recreating it every time like so:

list[i] = .....

Loop through the array and print out only the last item

Answer №1

Answer №2

Answer №3

Answer №4

Answer №5

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