John Sawyer's Prep Ruby Challenges

combinations.rb

@@ -0,0 +1,9 @@
+def combinations(arr1, arr2)
+  return_arr = []
+  arr1.each_with_index do |word1, index1|
+    arr2.each_with_index do |word2, index2|
+      return_arr << word1 + word2
+    end
+  end
+  return_arr
+end

counting.rb

@@ -0,0 +1,42 @@
+def counting(players, count)
+  def rotate_player(up, player, players)
+    if up
+      if player < players
+        player += 1
+      else
+        player = 1
+      end
+    else
+      if player > 1
+        player -= 1
+      else
+        player = players
+      end
+    end
+  end
+
+  up = true
+  player = 1
+
+  (1..count).each do |x|
+    #skip a player if count is divisible by 11
+    # if x % 11 == 0
+    #   player = rotate_player(up, player, players)
+    # end
+    #print number and corresponding number
+
+    puts "The number #{x} was spoken by player #{player}"
+
+    #change direction if divisible by seven
+    if x % 7 == 0
+      up = !up
+    end
+
+    player = rotate_player(up, player, players)
+
+    if x % 11 == 0
+      player = rotate_player(up, player, players)
+    end
+  end
+
+end

factorial.rb

@@ -0,0 +1,7 @@
+def factorial(num)
+  answer = 1
+  (1..num).each do |x|
+    answer *= x
+  end
+  answer
+end

overlap.rb

@@ -0,0 +1,13 @@
+def overlap(n, m)
+  #list of sides:
+  firstleft = n[0][0]
+  firstbottom = n[0][1]
+  firstright = n[1][0]
+  firsttop = n[1][1]
+  secondleft = m[0][0]
+  secondbottom = m[0][1]
+  secondright = m[1][0]
+  secondtop = m[1][1]
+
+  firstleft < secondright && firsttop > secondbottom && firstright > secondleft && firstbottom < secondtop
+end

power.rb

@@ -0,0 +1,7 @@
+def power(base,exponent)
+  answer = 1
+  exponent.times do
+    answer *= base
+  end
+  answer
+end

primes.rb

@@ -0,0 +1,5 @@
+def is_prime?(num)
+  return false if num <= 1
+  Math.sqrt(num).to_i.downto(2).each {|i| return false if num % i == 0}
+  true
+end

uniques.rb

@@ -0,0 +1,11 @@
+def uniques(x)
+  final = []
+  #loop over entire array
+  x.each_with_index do |v, i|
+      unless final.include?(v)
+        final.push(v)
+      end
+  end
+  #return array
+  final
+end