Add playground for linear search

Change Comparable to Equatable

Author: hollance

Linear Search/LinearSearch.playground/Contents.swift

@@ -0,0 +1,12 @@
+//: Playground - noun: a place where people can play
+
+func linearSearch<T: Equatable>(array: [T], _ object: T) -> Int? {
+  for (index, obj) in array.enumerate() where obj == object {
+    return index
+  }
+  return nil
+}
+
+let array = [5, 2, 4, 7]
+linearSearch(array, 2) 	// returns 1
+linearSearch(array, 3) 	// returns nil

Linear Search/LinearSearch.playground/contents.xcplayground

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
+<playground version='5.0' target-platform='osx'>
+    <timeline fileName='timeline.xctimeline'/>
+</playground>

Linear Search/LinearSearch.playground/timeline.xctimeline

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Timeline
+   version = "3.0">
+   <TimelineItems>
+   </TimelineItems>
+</Timeline>

Linear Search/LinearSearch.swift

@@ -1,4 +1,4 @@
-func linearSearch<T: Comparable>(array: [T], _ object: T) -> Int? {
+func linearSearch<T: Equatable>(array: [T], _ object: T) -> Int? {
   for (index, obj) in array.enumerate() where obj == object {
     return index
   }

Linear Search/README.markdown

@@ -15,7 +15,7 @@ We start by comparing the first number in the array, `5` with the number we're l
 Here is a simple implementation of insertion sort in Swift:
 
 ```swift
-func linearSearch<T: Comparable>(array: [T], _ object: T) -> Int? {
+func linearSearch<T: Equatable>(array: [T], _ object: T) -> Int? {
   for (index, obj) in array.enumerate() where obj == object {
     return index
   }