freeCodeCamp/guide/english/certifications/javascript-algorithms-and-d.../basic-javascript/golf-code/index.md

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2018-10-12 19:37:13 +00:00
---
title: Golf Code
---
![:triangular_flag_on_post:](https://forum.freecodecamp.com/images/emoji/emoji_one/triangular_flag_on_post.png?v=3 ":triangular_flag_on_post:") Remember to use <a>**`Read-Search-Ask`**</a> if you get stuck. Try to pair program ![:busts_in_silhouette:](https://forum.freecodecamp.com/images/emoji/emoji_one/busts_in_silhouette.png?v=3 ":busts_in_silhouette:") and write your own code ![:pencil:](https://forum.freecodecamp.com/images/emoji/emoji_one/pencil.png?v=3 ":pencil:")
### ![:checkered_flag:](https://forum.freecodecamp.com/images/emoji/emoji_one/checkered_flag.png?v=3 ":checkered_flag:") Problem Explanation:
In the game of golf each hole has a **par** meaning the average number of **strokes** a golfer is expected to make in order to sink the ball in a hole to complete the play. Depending on how far above or below **par** your **strokes** are, there is a different nickname.
Your function will be passed **par** and **strokes** arguments. You've to return the correct string according to this table which lists the strokes in order of priority; top (highest) to bottom (lowest):
Strokes | Return
:--------- | :-------------
1 | "Hole-in-one!"
<= par - 2 | "Eagle"
par - 1 | "Birdie"
par | "Par"
par + 1 | "Bogey"
par + 2 | "Double Bogey"
&gt;= par + 3 | "Go Home!"
**par** and **strokes** will always be numeric and positive.
* Change the code below `// Only change code below this line` and above `// Only change code above this line`.
* Ensure that you're editing the inside of the `golfScore` function.
* You will have to make the function return exactly the same string as shown shown in the table, depending on the value of the parameters **par** and **strokes** that are passed to your function.
## ![:speech_balloon:](https://forum.freecodecamp.com/images/emoji/emoji_one/speech_balloon.png?v=3 ":speech_balloon:") Hint: 1
`+number -number` can be used to increase or decrease a parameter in your condition.
> _try to solve the problem now_
## ![:speech_balloon:](https://forum.freecodecamp.com/images/emoji/emoji_one/speech_balloon.png?v=3 ":speech_balloon:") Hint: 2
You use `if / else if` chains to return different values in different scenarios.
> _try to solve the problem now_
## ![:speech_balloon:](https://forum.freecodecamp.com/images/emoji/emoji_one/speech_balloon.png?v=3 ":speech_balloon:") Hint: 3
Control the flow of your function based on the tables order of priority - top (highest) to bottom (lowest) to return matching string values.
> _try to solve the problem now_
## Spoiler Alert!
![warning sign](//discourse-user-assets.s3.amazonaws.com/original/2X/2/2d6c412a50797771301e7ceabd554cef4edcd74d.gif)
**Solution ahead!**
## ![:beginner:](https://forum.freecodecamp.com/images/emoji/emoji_one/beginner.png?v=3 ":beginner:") Basic Code Solution:
function golfScore(par, strokes) {
// Only change code below this line
if (strokes == 1){
return "Hole-in-one!";
} else if (strokes <= par -2){
return "Eagle";
} else if (strokes == par -1) {
return "Birdie";
} else if (strokes == par) {
return "Par";
} else if (strokes == par +1) {
return "Bogey";
} else if (strokes == par +2) {
return "Double Bogey";
} else {
return "Go Home!";
}
// Only change code above this line
}
// Change these values to test
golfScore(5, 4);
### Code Explanation:
* Compare the parameters **par** and **strokes** to return appropriate string values.
* `if / else if` chain is used for flow control.
* String "Go Home!" is returned for every condition where **strokes** is greater than or equal to **par + 3**.
## Alternative code solution:
```javascript
var names = ["Hole-in-one!", "Eagle", "Birdie", "Par", "Bogey", "Double Bogey", "Go Home!"];
function golfScore(par, strokes) {
// Only change code below this line
if (strokes == 1){
return names[0];
}
else if (strokes <= par-2){
return names[1];
}
else if (strokes == par -1){
return names[2];
}
else if (strokes == par){
return names[3];
}
else if (strokes == par +1){
return names[4];
}
else if (strokes == par +2){
return names[5];
}
else {return names[6];}
// Only change code above this line
}
// Change these values to test
golfScore(5, 4);
```
·Run at [repl.it](https://repl.it/@AdrianSkar/Basic-JS-Golf-code)
## Code explanation
Since we already have an array defined in the variable `names` we can take advantage of it and use it for our return statements using indexes (eg: `names[0] is the first one`). That way, if you ever need to change a specific result you wouldn't need to look for it inside the function, it'd be at the beginning, in your array.
## ![:sunflower:](https://forum.freecodecamp.com/images/emoji/emoji_one/sunflower.png?v=3 ":sunflower:") Intermediate Code Solution:
(Using Multiple Conditional (Ternary) Operators)
```js
function golfScore(par, strokes) {
return (strokes == 1) ? names[0] :
(strokes <= par - 2) ? names[1] :
(strokes == par - 1) ? names[2] :
(strokes == par) ? names[3] :
(strokes == par + 1) ? names[4] :
(strokes == par + 2) ? names[5] :
(strokes >= par + 3) ? names[6] :
"Change Me";
}
```
![:rocket:](https://forum.freecodecamp.com/images/emoji/emoji_one/rocket.png?v=3 ":rocket:") <a href='https://repl.it/@greggubarev/Basic-JS-Golf-code1' target='_blank' rel='nofollow'>Run Code</a>
2018-10-12 19:37:13 +00:00
### Resources
* <a href='https://en.wikipedia.org/wiki/Golf' target='_blank' rel='nofollow'>Golf</a>
* <a href='http://www.freecodecamp.com/challenges/chaining-if-else-statements' target='_blank' rel='nofollow'>Challenge: Chaining If Else Statements</a>
* <a href='http://www.freecodecamp.com/challenges/comparison-with-the-greater-than-equal-to-operator' target='_blank' rel='nofollow'>Challenge: Comparison with the Greater Than Equal To Operator</a>
* <a href='http://www.freecodecamp.com/challenges/comparison-with-the-less-than-equal-to-operator' target='_blank' rel='nofollow'>Challenge: Comparison with the Less Than Equal To Operator</a>
* ["Array" - *MDN JavaScript reference*](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array)
* <a href='https://learn.freecodecamp.org/javascript-algorithms-and-data-structures/basic-javascript/use-multiple-conditional-ternary-operators/' target='_blank' rel='nofollow'>Use Multiple Conditional (Ternary) Operators</a>