how to find index of duplicates items in array

Question

I am having a with graph, i need to remove duplicates values from array and "0" as well and i want to adjust array according to that for example

extension Array where Element: Equatable {
 var unique: [Element] {
 var uniqueValues: [Element] = []
 forEach { item in
 if !uniqueValues.contains(item) {
 uniqueValues += [item]
 }
 }
 return uniqueValues
 }
}
let speed = [0, 10, 20, 20, 40, 50, 50 ,50, 80, 90, 100]
let time = ["9", "10", "11", "12", "13", "15", "16", "17", "18", "19", "20"]
speed.unique // Return Only Unique Values 

Now i want my time array to be updated. Example Index : 0, 3 - is removed from speed i want to remove index 0, 3 from time as well

• rmaddy: Use one array of struct where the struct has speed and time properties. Then you much more easily sort and filter the array of struct. When done you could create the two final arrays from the final array of struct.
• istorry: i am using speed as struct and time as [String], but no luck :(
• rmaddy: Please read my comment again. You want one struct with both values and a single array.

Answer 1

You can do it this way:

let speed = [ 0, 10, 20, 20, 40, 50, 50, 50, 80, 90, 100]
let time = ["9", "10", "11", "12", "13", "15", "16", "17", "18", "19", "20"]
var sp = [Int]()
var tm = [String]()
for (i, x) in speed.enumerated() {
 if !sp.contains(x) {
 sp.append(x)
 tm.append(time[i])
 }
}
print(sp) //[ 0, 10, 20, 40, 50, 80, 90, 100]
print(tm) //["9", "10", "11", "13", "15", "18", "19", "20"]

Choosing an appropriate type for time is advisable.

It is recommended in object-oriented programming to have speed and time as properties of a struct:

struct Mover {
 let speed: Int
 let time : TimeInterval
}

For example given this array:

let movers = [Mover(speed: 0, time: 9),
 Mover(speed: 10, time: 10),
 Mover(speed: 20, time: 11),
 Mover(speed: 20, time: 12),
 Mover(speed: 40, time: 13),
 Mover(speed: 50, time: 15),
 Mover(speed: 50, time: 16),
 Mover(speed: 50, time: 17),
 Mover(speed: 80, time: 18),
 Mover(speed: 90, time: 19),
 Mover(speed: 100, time: 20)]

You could keep the elements with a unique speed this way:

var speeds = Set<Int>()
let moversUniqueSpeed = movers.filter { speeds.insert(0ドル.speed).inserted }

• istorry: i am so dumb why didn't i thought about this, Thank you very much.