Exercise taking the position of the array

Question

I’m doing an exercise but I can’t go through all the necessary validations.

Write the function "medalText(number)", which takes a number as a parameter, using only an "if".

You have to return the medal that corresponds to the first positions of a competition:

• medalleDecordoComsto (1) - "gold"
• medalleDecordoComsto (2) - "silver"
• medalleDecordoComsto (3) - "bronze"
• medalleDecordoComPost (4) - "nothing"
• medalleDecordoComPost (15) - "nothing"
• medalleDecordoComsto (0) - "nothing"

var posicoes = ["nada", "ouro", "prata", "bronze"];

function medalhaDeAcordoComPosto(numero){
  return posicoes[numero];
}

console.log(medalhaDeAcordoComPosto(15));

My biggest question is how to return "nothing" when I pass parameter 0 or higher than 3.

Answer 1

Hello @Raphael, it seems to me that your exercise aims to make you understand two things.

1. That the indexes have their beginning in 0.
2. Identify/Work with the size of a Array.
   _Array.length

---

I see the first you ever killed,
^{as it is placing as the first element of its Array the string "nada"}

So for you to finish your exercise just you do the checking (if) using the array size (posicoes.length).

Important detail, posicoes.length is the amount of elements in your Array posicoes, is not the index of the last element.
Knowing this just add to the check if( numero >= posicoes.length ) return "nada";

var posicoes = ["nada", "ouro", "prata", "bronze"];

function medalhaDeAcordoComPosto(numero){
  if( numero >= posicoes.length ) return "nada";

  return posicoes[numero];
}

console.log(0,medalhaDeAcordoComPosto(0));
console.log(1,medalhaDeAcordoComPosto(1));
console.log(2,medalhaDeAcordoComPosto(2));
console.log(3,medalhaDeAcordoComPosto(3));
console.log(4,medalhaDeAcordoComPosto(4));
console.log(5,medalhaDeAcordoComPosto(5));
console.log(15,medalhaDeAcordoComPosto(15));

^{Note: You may need to add if a check for negative numbers, leaving +/- like this: if( numero >= posicoes.length || numero < 0)}

---

Now let’s use the index 0

In this other example we will create an array only with prizes, so we will have:

var posicoes = ["ouro", "prata", "bronze"];

In your job we’ll do the following:

• Diminish 1 in the reported value.
  ^{That way if the person calls the function by passing the 1 he will treat as 0.}

• Make a if to verify:

  • if the value is less than 0, that is, negative index and invalidity.
  • Or if the value is greater than to amount of elements in the array - 1, that is, the last index of the array. (posicoes.length-1)

var posicoes = ["ouro", "prata", "bronze"];

function medalhaDeAcordoComPosto(numero){
  numero -= 1;  /// ; isso é a msm coisa que `numero = numero - 1;`
  if( numero < 0 || numero > posicoes.length-1 ) return "nada";

  return posicoes[numero];
}

console.log(0,medalhaDeAcordoComPosto(0));
console.log(1,medalhaDeAcordoComPosto(1));
console.log(2,medalhaDeAcordoComPosto(2));
console.log(3,medalhaDeAcordoComPosto(3));
console.log(4,medalhaDeAcordoComPosto(4));
console.log(5,medalhaDeAcordoComPosto(5));
console.log(15,medalhaDeAcordoComPosto(15));

Answer 2

Icaro Martins' answer is correct and perfectly answers the question. However, for those interested, I just wanted to add a minimalist solution using `||` and a Arrow Function. Check out:

const medalhaDeAcordoComPosto = numero => posicoes[numero] || "nada";

Answer 3

Follow my solution to the problem:

var posicoes = ['nada', 'ouro', 'prata', 'bronze'];

function medalhaDeAcordoComPosto(numero){
   if( numero >= posicoes.length ){
     return ("nada");
   } else{
     return posicoes[numero];    
   } 
  
}


console.log(medalhaDeAcordoComPosto(100));

Answer 4

Bro, I picked up your know why I just didn’t know how to make the start and worked with if and Else to treat numbers <0 and >3 binds:

var medal = ["nada", "ouro", "prata", "bronze"];

function medalhaDeAcordoComPosto(num){
    if (num >3 || num <0){
    return medal[0];
  }
  else{
    return medal[num];
  }
}

Answer 5

Hello, Raphael!

Then... The function you created returns an element of the array. Therefore, the (number) of the function must be a value related to the position of an array.

For example, the value "gold" is at position 1 of the array. So, if you want to print the "gold" element on the screen, you have to put the code as follows:

var posicoes = ["nada", "ouro", "prata", "bronze"];

function medalhaDeAcordoComPosto(numero){
  return posicoes[numero];
}

console.log(medalhaDeAcordoComPosto(1));

Answer 6

Follows a solution successfully executed:

function medalhaDeAcordoComPosto(numero){

  var posto=["ouro","prata","bronze","nada"];

  var posicao=numero-1;

  if (numero ==0 || numero >= posto.length){
     posicao=3;
    return posto[posicao];
  } else{

  return posto[posicao];
  }
}

Answer 7

function medalhaDeAcordoComPosto(numero) {
  var medalhas = ['nada', 'ouro', 'prata', 'bronze', 'nada', 'nada']

  if(medalhas.indexOf(medalhas[numero]) == numero) {
    return medalhas[numero]
  } else {
    return medalhas[3, 4]
  }
}

I do not know if you have already solved, but follows resolution... (I hope I helped) Hug!

Answer 8

I would do so...

function medalhaDeAcordoComPosto(posto){
var medalhas = ["nada","ouro","prata","bronze"];
if((posto > 0) && (posto < 4)){
    return console.log(medalhas[posto]);
}else{
    return console.log(medalhas[0]);
}

}