Curious to know if there is a better way to do this. I have an array of arrays that contain integers. All the integers are unique. I want to search for a given number and return the index of the first array. I don't care what the index is of the array containing the numbers.

This does what I want but I'm new to swift and figured there is a better way.

```
let arr:[[Int]] = [[0], [1], [2, 3], [4], [11, 12, 13, 14, 15, 16], [5], [6], [7], [8], [9], [10]]

var t = -1
for q in arr {
    t += 1
    if let x = q.index(of: 13) { // <-- looking for the index that contains 13
        print ("t: \(t)") // <-- this is what I want. Returns '4'
    }
}

```