Answered the questions about the big O for each snippet

README.md

@@ -14,7 +14,7 @@
 
 ### Problems for you
 
-Snippet 1 - Big O:
+Snippet 1 - Big O: O(n), because in the worst case, we will iterate through the array once.
 ```ruby
 def largest?(array, value)
   array.each do |item|
@@ -24,7 +24,7 @@ def largest?(array, value)
 end
 ```
 
-Snippet 2 - Big O:
+Snippet 2 - Big O: O(n), because while we have two each loops, they are not nested. So O(n + n) = O(n)
 ```ruby
 def info_dump(customers)
   puts "Customer Names: "
@@ -38,14 +38,14 @@ def info_dump(customers)
 end
 ```
 
-Snippet 3 - Big O:
+Snippet 3 - Big O: O(1), because no matter how big the array is, we're only checking one element from it (the first).
 ```ruby
 def first_element_is_red?(array)
   array[0] == 'red' ? true : false
 end
 ```
 
-Snippet 4 - Big O:
+Snippet 4 - Big O: O(n^2), because we have a nested each_with_index loop. We will be looping through the whole array for each element of the array.
 ```ruby
 def duplicates?(array)
   array.each_with_index do |item1, index1|
@@ -58,7 +58,7 @@ def duplicates?(array)
 end
 ```
 
-Snippet 5 - Big O:
+Snippet 5 - Big O: O(n * m), because though the each loops don't depend on each other, they each run in linear time.
 ```ruby
 words = [chocolate, coconut, rainbow]
 endings = [cookie, pie, waffle]
@@ -70,7 +70,7 @@ words.each do |word|
 end
 ```
 
-Snippet 6 - Big O:
+Snippet 6 - Big O: O(n), because we are looping through the array once.
 ```ruby
 numbers = # some array (you don't know contents)
 
@@ -79,7 +79,7 @@ def print_array(array)
 end
 ```
 
-Snippet 7 - Big O:
+Snippet 7 - Big O: O(n^2), because in the worst case, for each element we're sorting, we might have to compare it to every other element in the array again.
 ```ruby
 # this is insertion sort
 (2...num.length).each do |j|
@@ -93,7 +93,7 @@ Snippet 7 - Big O:
 end
 ```
 
-Snippet 8 - Big O:
+Snippet 8 - Big O: O(n^2), because in the worst case, for each element we're sorting, we might have to compare it to every other element in the array again.
 ```ruby
 # this is selection sort
 n.times do |i|