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JavaScript

Posted by jason chan
jason chan
31,009 Points

Total Difference algo javascript

  • With that done, compare the difference between current user's scores against those from other users, question by question. Add up the differences to calculate the totalDifference.
    • Example:
    • User 1: [5, 1, 4, 4, 5, 1, 2, 5, 4, 1]
    • User 2: [3, 2, 6, 4, 5, 1, 2, 5, 4, 1]
    • Total Difference: 2 + 1 + 2 = 5
    • Remember to use the absolute value of the differences. Put another way: no negative solutions! Your app should calculate both 5-3 and 3-5 as 2, and so on.
    • The closest match will be the user with the least amount of difference.

2 Answers

Thomas Nilsen
Thomas Nilsen
14,957 Points

Do you need help or is this some sort of challenge? Anyway:

var arr1 = [5, 1, 4, 4, 5, 1, 2, 5, 4, 1]; 
    arr2 = [3, 2, 6, 4, 5, 1, 2, 5, 4, 1], 
    totalDifference = 0;

for (var i = 0; i < arr1.length; i++) {
    totalDifference += Math.abs(arr1[i] - arr2[i]);
}

console.log(totalDifference); // print 5
jason chan
jason chan
31,009 Points

Neverminds. I figured it outs. Thank bro. ^_^ Much appreciated.

jason chan
jason chan
31,009 Points
jason chan
jason chan
31,009 Points

thanks thomas for trying

// data
// but pretend it's not all jason chan and the same image. Getting the match from this giant array of objects.
var friendsData = [
    {
        "name" : "Jason Chan",
        "photo" : "https://pbs.twimg.com/profile_images/621921614377058304/ailqyj6j.jpg",
        "scores" : [1,2,3,4,5,1,1,1,1]
    },
    {
        "name" : "Jason Chan",
        "photo" : "https://pbs.twimg.com/profile_images/621921614377058304/ailqyj6j.jpg",
        "scores" : [3,2,3,4,5,6,7,5,1]
    },
    {
        "name" : "Jason Chan",
        "photo" : "https://pbs.twimg.com/profile_images/621921614377058304/ailqyj6j.jpg",
        "scores" : [5,2,3,4,5,6,7,5,1]
    },
    {
        "name" : "Jason Chan",
        "photo" : "https://pbs.twimg.com/profile_images/621921614377058304/ailqyj6j.jpg",
        "scores" : [5,5,6,7,5,6,7,5,1]
    }
]

// i need this output though
// NEED this output below or return
var match = {
                "name" : "Jason Chan",
                "photo" : "https://pbs.twimg.com/profile_images/621921614377058304/ailqyj6j.jpg",
                "scores" : [1,2,3,4,5,1,1,1,1]
            };