diff --git a/01-hello.rb b/01-hello.rb
index e0e7bbf..85da3da 100644
--- a/01-hello.rb
+++ b/01-hello.rb
@@ -5,4 +5,5 @@
 
 # ...
 
-puts "(请替换成最后的答案)"
\ No newline at end of file
+puts "Hello，" + your_name
+#puts "Hello, #{your_name}"
diff --git a/02-variable.rb b/02-variable.rb
index a5a4753..8079b95 100644
--- a/02-variable.rb
+++ b/02-variable.rb
@@ -6,8 +6,10 @@
 puts "a 是 #{a}"
 puts "b 是 #{b}"
 
+c = a
+a = b
+b = c
 # ...
 
 puts "a 应该是 2，现在是 #{a}"
 puts "b 应该是 1，现在是 #{b}"
-
diff --git a/03-triangle.rb b/03-triangle.rb
index fafec03..130c667 100644
--- a/03-triangle.rb
+++ b/03-triangle.rb
@@ -6,6 +6,7 @@
 print "请输入直角三角形的底边，然后按 Enter: "
 b = gets
 
+c = (b.to_i * a.to_i)/2
 # .....
 
-puts "直角三角形的面积是: _________"
\ No newline at end of file
+puts "直角三角形的面积是: ___#{c}_____"
diff --git a/04-pizzas.rb b/04-pizzas.rb
index 4c2521f..8034c6a 100644
--- a/04-pizzas.rb
+++ b/04-pizzas.rb
@@ -6,7 +6,9 @@
 print "请输入有多少人要吃，然后按 Enter: "
 people = gets
 
+a = pizzas.to_i/people.to_i
+b = pizzas.to_i % people.to_i
 # .....
 
-puts "每人可分得几片: _________ 片"
-puts "还剩下几片: _________ 片"
\ No newline at end of file
+puts "每人可分得几片: ____#{a}_____ 片"
+puts "还剩下几片: ____#{b}_____ 片"
diff --git a/05-bmi.rb b/05-bmi.rb
index 67efdff..49afb61 100644
--- a/05-bmi.rb
+++ b/05-bmi.rb
@@ -10,8 +10,19 @@
 print "请输入您的身高(厘米)，然后按 Enter: "
 height = gets
 
+a = weight.to_f/(height.to_f*height.to_f)
+
+  if a<18.5
+    b = "体重过轻"
+  elsif a>24
+    b = "体重过重"
+  elsif a>18.5 && a<24
+
+    b = "正常"
+  end
+
 # .....
 
-puts "您的 BMI 是: _________"
+puts "您的 BMI 是: ______#{a}___"
 
-puts "您的 BMI 结果是: _________(过轻或正常或过重)"
\ No newline at end of file
+puts "您的 BMI 结果是: ____#{b}____(过轻或正常或过重)"
diff --git a/06-interger-positive.rb b/06-interger-positive.rb
index a240f5f..b90f3a4 100644
--- a/06-interger-positive.rb
+++ b/06-interger-positive.rb
@@ -2,9 +2,26 @@
 
 
 print "请输入一个整数，然后按 Enter: "
-x = gets
+x = gets.to_i
 
+if x > 0
+  a = "正数"
+elsif x < 0
+  a = "负数"
+elsif x == 0
+  a = "零"
+end
+
+b = x%2
+
+if x < 0
+  c = "不是奇数也不是偶数"
+elsif b == 0
+  c = "偶数"
+elsif b == 1
+  c = "奇数"
+end
 # ....
 
-puts "这个数是_____ (正数或零或负数)"
-puts "这个数是_____ (偶数或奇数)"
\ No newline at end of file
+puts "这个数是____#{a}_ (正数或零或负数)"
+puts "这个数是____#{c}_ (偶数或奇数)"
diff --git a/07-abcde.rb b/07-abcde.rb
index 5d0c8c3..1c080c6 100644
--- a/07-abcde.rb
+++ b/07-abcde.rb
@@ -9,14 +9,32 @@
 #     当 z < 0 输出 "E"
 
 print "请输入一个整数x，然后按 Enter: "
-x = gets
+x = gets.to_i
 
 print "请输入一个整数y，然后按 Enter: "
-y = gets
+y = gets.to_i
 
 print "请输入一个整数z，然后按 Enter: "
-z = gets
+z = gets.to_i
 
+
+ if x < 0
+   t ="A"
+elsif x > 0
+  if y > 0
+    if z > 0
+      t = "B"
+    elsif z < 0
+      t = "C"
+    end
+  elsif y < 0
+    if z > 0
+      t = "D"
+    elsif z < 0
+      t = "E"
+    end
+  end
+ end
 # ....
 
-puts "结果是________(A或B或C或D或E)"
\ No newline at end of file
+puts "结果是___#{t}_____(A或B或C或D或E)"
diff --git a/08-find-max.rb b/08-find-max.rb
index 9e6e643..97e2c44 100644
--- a/08-find-max.rb
+++ b/08-find-max.rb
@@ -1,14 +1,29 @@
 # 题目: 使用者输入 x,y,z，请输出三个数中最大的数
 
 print "请输入一个数字x，然后按 Enter: "
-x = gets
+x = gets.to_i
 
 print "请输入一个数字y，然后按 Enter: "
-y = gets
+y = gets.to_i
 
 print "请输入一个数字z，然后按 Enter: "
-z = gets
+z = gets.to_i
+
+
+ if x > y
+    if x > z
+      t = "x"
+    else
+      t = "z"
+    end
+ else
+   if y > z
+     t = "y"
+   else
+     t = "z"
+   end
+ end
 
 # ....
 
-puts "最大的数是 ________(x或y或z)"
\ No newline at end of file
+puts "最大的数是 ____#{t}____(x或y或z)"
diff --git a/09-function.rb b/09-function.rb
index b1f922d..9dc946a 100644
--- a/09-function.rb
+++ b/09-function.rb
@@ -1,15 +1,16 @@
 # 题目: 输入直角三角形的宽和高，输出三角形的面积
 
 def calculate_area(a, b)
+  return "#{b * a / 2}"
   # ....
 end
 
 print "请输入直角三角形的高，然后按 Enter: "
-a = gets
+a = gets.to_i
 
 print "请输入直角三角形的底边，然后按 Enter: "
-b = gets
+b = gets.to_i
 
 answer = calculate_area(a,b)
 
-puts "直角三角形的面积是: #{answer}"
\ No newline at end of file
+puts "直角三角形的面积是: #{answer}"
diff --git a/10-function.rb b/10-function.rb
index bb450fb..f39136e 100644
--- a/10-function.rb
+++ b/10-function.rb
@@ -1,19 +1,32 @@
 # 题目: 使用者输入 x,y,z，请输出三个数中最大的数
 
 def find_max(x, y, z)
+  if x > y
+     if x > z
+       t = "x"
+     else
+       t = "z"
+     end
+  else
+    if y > z
+      t = "y"
+    else
+      t = "z"
+    end
+  end
 end
 
 print "请输入一个数字x，然后按 Enter: "
-x = gets
+x = gets.to_i
 
 print "请输入一个数字y，然后按 Enter: "
-y = gets
+y = gets.to_i
 
 print "请输入一个数字z，然后按 Enter: "
-z = gets
+z = gets.to_i
 
 # ....
 
 answer = find_max(x,y,z)
 
-puts "最大的数是 #{answer}"
\ No newline at end of file
+puts "最大的数是 #{answer}"
diff --git a/11-seven.rb b/11-seven.rb
index 26c221d..e098bd6 100644
--- a/11-seven.rb
+++ b/11-seven.rb
@@ -2,8 +2,11 @@
 
 i = 1
 while ( i <= 100 )
-
+  if i % 7 == 0
+    puts i
+  end
   # ....
 
   i+=1
-end
\ No newline at end of file
+
+end
diff --git a/12-sum-even.rb b/12-sum-even.rb
index 73879bb..e09e554 100644
--- a/12-sum-even.rb
+++ b/12-sum-even.rb
@@ -4,10 +4,12 @@
 total = 0
 
 while ( i <= 100 )
-
+  if i % 2 == 0
+     total += i
+  end
   # ....
 
   i+=1
 end
 
-puts total
\ No newline at end of file
+puts total
diff --git a/13-nn.rb b/13-nn.rb
index ac0a43b..49ca470 100644
--- a/13-nn.rb
+++ b/13-nn.rb
@@ -1,11 +1,15 @@
 # 题目: 输入一个数字 N，输出 N * N 乘法表
 
 print "请输入数字 N，然后按 Enter: "
-n = gets
-
-# while ( ... )
-#   while ( ...)
-#
-#   end
-# end
+n = gets.to_i
 
+i = 0
+j = 0
+ while ( i <= n )
+   while ( j <= n)
+     puts "#{i} x #{j} = #{i * j}"
+      j += 1
+   end
+   j = 0
+   i += 1
+ end
diff --git a/14-prime.rb b/14-prime.rb
index 8cf1692..2aa73ab 100644
--- a/14-prime.rb
+++ b/14-prime.rb
@@ -1,6 +1,17 @@
 # 输入一个数字 N，请检查是不是质数
 
 def is_prime(n)
+  i = 2
+  if n < 2
+    return false
+  end
+  while (i < n)
+    if n % i == 0
+      return false
+    end
+    i += 1
+  end
+  return true
 # ....
 end
 
diff --git a/15-guess-number.rb b/15-guess-number.rb
index 48f9dca..5ca1dcf 100644
--- a/15-guess-number.rb
+++ b/15-guess-number.rb
@@ -4,14 +4,16 @@
 
 while (true)
   print "请猜一个 0~99 的数字 N，然后按 Enter: "
-  n = gets
-
-  #puts "太低了，再猜一次"
-  #puts "太高了，再猜一次"
-
-  if n.to_i == target
+  n = gets.to_i
+  if n < target
+    puts "太低了，再猜一次"
+  elsif n > target
+    puts "太高了，再猜一次"
+  elsif  n.to_i == target
     puts "恭喜猜中啦! "
     break
-  end
 
-end
\ No newline at end of file
+  end
+  #puts "太低了，再猜一次"
+  #puts "太高了，再猜一次"
+end
diff --git a/16-array-sum.rb b/16-array-sum.rb
index 9b4910b..59bd391 100644
--- a/16-array-sum.rb
+++ b/16-array-sum.rb
@@ -1,11 +1,17 @@
 # 给定一阵列内含数字，输出最大值
 
 def find_max(array)
+  x = 0
+  array.each do |i|
+    if i > x
+        x = i
+    end
+  end
+  return x
   #....
 end
 
-arr = [8, 12, 36, 53, 9, 75, 3, 71, 59, 88]
+arr = [8, 12, 36, 53, 9, 75, 3, 71, 59, 88,]
 
 max = find_max(arr)
 puts "Max is #{max}" # 应该是 88
-
diff --git a/17-array-stats.rb b/17-array-stats.rb
index 0af81bb..dc2fb22 100644
--- a/17-array-stats.rb
+++ b/17-array-stats.rb
@@ -12,9 +12,48 @@
   end
 end
 
+
 puts arr.to_s
 
-puts "总和是 _____"
-puts "平均是 _____"
-puts "最大值是 _____"
-puts "最小值是 _____"
\ No newline at end of file
+def total(array)
+  t = 0
+  array.each do |i|
+    t = t + i
+  end
+    return t
+end
+
+def average(array)
+  a = total(array)
+  b = total(array)/array.size
+end
+
+def find_max(array)
+  x = 0
+  array.each do |i|
+    if i > x
+        x = i
+    end
+ end
+ return x
+end
+
+def find_min(array)
+  x = array[0]
+  array.each do |i|
+    if i < x
+       x = i
+    end
+  end
+  return x
+end
+
+max = find_max(arr)
+min = find_min(arr)
+
+puts "总和是 _#{total(arr)}____"
+puts "平均是 __#{average(arr)}___"
+puts "最大值是 _#{max}___"
+puts "最小值是 _#{min}____"
+
+#也可以直接调用数组对象的max(最大)和min(最小)方法
diff --git a/18-square.rb b/18-square.rb
index 226e1c1..8f1249f 100644
--- a/18-square.rb
+++ b/18-square.rb
@@ -3,8 +3,21 @@
 arr = []
 
 print "请输入数字 N，然后按 Enter: "
-n = gets
+n = gets.to_i
 
+# 方法一 ：
+for i in 0..n-1
+  arr << i * i
+end
+
+#方法二 ：
+=begin
+i = 0
+while (i < n)
+  arr << i * i
+  i += 1
+end
+=end
 # ...
 
-puts arr.to_s
\ No newline at end of file
+puts arr.to_s
diff --git a/19-filter.rb b/19-filter.rb
index ef7e515..b3fe857 100644
--- a/19-filter.rb
+++ b/19-filter.rb
@@ -1,9 +1,16 @@
 # 给定一阵列内含数字，输出另一个数组只包含偶数
 
 def filter_even(arr)
+  a = []
+  for i in arr
+    if i % 2 == 0
+      a << i
+    end
+  end
+    return a
   #...
 end
 
 arr =  [7, 68, 42, 46, 9, 91, 77, 46, 86, 1]
 
-puts filter_even(arr).to_s # 应该是 [68, 42, 46, 46, 86]
\ No newline at end of file
+puts filter_even(arr).to_s # 应该是 [68, 42, 46, 46, 86]
diff --git a/20-sorting.rb b/20-sorting.rb
index 5f82c08..3710012 100644
--- a/20-sorting.rb
+++ b/20-sorting.rb
@@ -2,10 +2,20 @@
 # Hint: 可用 arr.sort 排序，和 arr.uniq 去除重复
 
 def filter_even(arr)
-  #...
+  a = []
+  for i in arr
+    if i % 2 == 0
+      a << i
+    end
+  end
+    a = a.uniq
+    return a.sort
+
 end
 
+
+
 arr =  [7, 68, 42, 46, 9, 91, 77, 46, 86, 1]
 
 
-puts "________" # 应该是 [42, 46, 68, 86]
\ No newline at end of file
+puts "__#{filter_even(arr)}______" # 应该是 [42, 46, 68, 86]
diff --git a/21-selection-sort.rb b/21-selection-sort.rb
index e5e7eae..83e6c28 100644
--- a/21-selection-sort.rb
+++ b/21-selection-sort.rb
@@ -3,10 +3,26 @@
 
 def selection_sort(arr)
   #...
+
+  k = 0
+  array = []
+  x = 0
+  while x < arr.size
+    a = arr[0]
+    arr.each_with_index do |i, j|
+      if i <= a
+          a = i
+          k = j
+      end
+    end
+    array << a
+    arr.delete_at(k)
+  end
+    return array
 end
 
 arr =  [7, 68, 42, 46, 9, 91, 77, 46, 86, 1]
 
 answer = selection_sort(arr)
 
-puts answer.to_s # 应该是 [1, 7, 9, 42, 46, 46, 68, 77, 86, 91]
\ No newline at end of file
+puts answer.to_s # 应该是 [1, 7, 9, 42, 46, 46, 68, 77, 86, 91]
diff --git a/22-missing.rb b/22-missing.rb
index 6898714..66f9a0d 100644
--- a/22-missing.rb
+++ b/22-missing.rb
@@ -1,7 +1,14 @@
 # 给定一阵列内含数字，请输出 0~9 中不见的数字
 
 def find_missing(arr)
-  # ...
+  array = [0,1,2,3,4,5,6,7,8,9]
+  answer = []
+  array.each do |i|
+    unless arr.include?(i)
+      answer << i
+    end
+  end
+  return answer
 end
 
 answer = find_missing( [2,2,1,5,8,4] )
diff --git a/23-hash-max.rb b/23-hash-max.rb
index 6fb227e..e799656 100644
--- a/23-hash-max.rb
+++ b/23-hash-max.rb
@@ -1,7 +1,15 @@
 # 给定一 Hash，输出有最大 value 的 key
 
 def find_max(hash)
-  # ...
+  i = 0
+  k = ""
+  hash.each do |key, value|
+    if value > i
+      i = value
+      k = key
+    end
+  end
+  return k
 end
 
 h = {
@@ -15,5 +23,3 @@ def find_max(hash)
 answer = find_max(h)
 
 puts "有最大 value 的是 #{answer}" # 应该是 d
-
-
diff --git a/24-hash-even.rb b/24-hash-even.rb
index 9da9605..82dd45f 100644
--- a/24-hash-even.rb
+++ b/24-hash-even.rb
@@ -2,8 +2,14 @@
 
 def find_even_keys(hash)
 
-  # ... (请回传一个数组)
-
+  i = []
+  hash.each do |key, value|
+    if value % 2 == 0
+      i << key
+    end
+  end
+
+  return i
 end
 
 h = {
@@ -17,5 +23,3 @@ def find_even_keys(hash)
 answer = find_even_keys(h)
 
 puts "有偶数 value 的 keys 有 #{answer}" # 应该是数组 [b,d,e]
-
-
diff --git a/25-hash-count.rb b/25-hash-count.rb
index 2167335..cb050ca 100644
--- a/25-hash-count.rb
+++ b/25-hash-count.rb
@@ -4,7 +4,11 @@ def count(arr)
   h = {}
 
   arr.each do |i|
-    # ...
+    if h[i]
+      h[i] += 1
+    else
+      h[i] = 1
+    end
   end
 
   return h # 回传一个 hash
@@ -15,4 +19,3 @@ def count(arr)
 answer = count(arr)
 
 puts answer # 答案应该是 {"a"=>3, "d"=>6, "c"=>5, "b"=>1, "e"=>5}
-
diff --git a/26-hash-filter.rb b/26-hash-filter.rb
index 51ade64..c97e609 100644
--- a/26-hash-filter.rb
+++ b/26-hash-filter.rb
@@ -8,9 +8,29 @@
   { "name" => "Vincent", "age" => 6 },
 ]
 
+def under_age(arr)
+  array = []
+  k = 0
+  x = 0
+  while x < arr.size
+    a = arr[0]["age"]
+    arr.each_with_index do |i, j|
+      if i["age"] <= a
+          a = i["age"]
+          k = j
+      end
+    end
+    if arr[k]["age"] > 18
+      array << arr[k]
+    end
+    arr.delete_at(k)
+  end
+  return array
+end
+
 # ....
 
-puts "所有成年人，并由小到大: _________"
+puts "所有成年人，并由小到大: _#{under_age(arr)}________"
 
 # 答案应该是
 #[
diff --git a/27-class.rb b/27-class.rb
index 8cec2c9..8c110ed 100644
--- a/27-class.rb
+++ b/27-class.rb
@@ -1,5 +1,9 @@
 class Person
-  # ...
+  attr_accessor :first_name, :last_name
+
+  def greet
+    puts "Hi, #{@first_name} #{@last_name}"
+  end
 end
 
 p1 = Person.new
@@ -11,6 +15,3 @@ class Person
 p2.first_name = "William"
 p2.last_name = "Zhang"
 p2.greet # 输出 "Hello, William Zhang"
-
-
-
diff --git a/28-word-count.rb b/28-word-count.rb
index 2643123..2e52ec1 100644
--- a/28-word-count.rb
+++ b/28-word-count.rb
@@ -1,5 +1,22 @@
 # 请打开 wordcount.txt，计算每个单字出现的次数
 
 doc = File.read("wordcount.txt")
+arr = doc.gsub(/[.,]/ ,"").split(" ")
 
+
+def count(arr)
+  h = {}
+  arr.each do |i|
+    if h[i]
+      h[i] += 1
+    else
+      h[i] = 1
+    end
+  end
+  return h
+end
+
+answer = count(arr)
 # ...
+
+puts answer
diff --git a/29-todos.rb b/29-todos.rb
index 0bddde2..c9d3968 100644
--- a/29-todos.rb
+++ b/29-todos.rb
@@ -17,17 +17,29 @@
 
   if command == "add"
     print "请输入代办事项: "
+    add = gets.chomp
+    todos << add
+    puts todos
+
     # ...
   elsif command == "remove"
     print "请输入要删除的编号: "
+    remove = gets.to_i
+      todos.delete_at(remove)
+    puts todos
     # ...
   elsif command == "save"
     puts "存盘离开"
+    File.open("todos.txt", "w+") do |f|
+       todos.each do |i|
+         f << i
+         f << "\n"
 
+       end
+      end
     # ...
     break;
   else
     puts "看不懂，请再输入一次"
   end
 end
-
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..8545d1a
--- /dev/null
+++ b/README.md
@@ -0,0 +1 @@
+编程基础练习作业
diff --git a/todos.txt b/todos.txt
index 4757e85..b33a4f3 100644
--- a/todos.txt
+++ b/todos.txt
@@ -2,3 +2,6 @@ Buy book
 Go Shopping
 Walk
 Gogo
+wei
+yue
+yan