09

01-hello.rb

@@ -5,4 +5,4 @@
 
 # ...
 
-puts "(请替换成最后的答案)"
+puts "hollo, #{your_name}"

02-variable.rb

@@ -8,6 +8,5 @@
 
 # ...
 
-puts "a 应该是 2，现在是 #{a}"
-puts "b 应该是 1，现在是 #{b}"
-
+puts "a 应该是 #{a}，现在是 #{b}"
+puts "b 应该是 #{b}，现在是 #{a}"

03-triangle.rb

@@ -7,5 +7,5 @@
 b = gets
 
 # .....
-
-puts "直角三角形的面积是: _________"
+c = a.to_i * b.to_i / 2
+puts "直角三角形的面积是: #{c}"

04-pizzas.rb

@@ -8,5 +8,7 @@
 
 # .....
 
-puts "每人可分得几片: _________ 片"
-puts "还剩下几片: _________ 片"
+a = pizzas.to_i / people.to_i
+b = pizzas.to_i % people.to_i
+puts "每人可分得几片: #{a} 片"
+puts "还剩下几片: #{b} 片"

05-bmi.rb

@@ -12,6 +12,18 @@
 
 # .....
 
-puts "您的 BMI 是: _________"
+a = weight.to_i
+b = height.to_f / 100
+c = a / (b * b)
 
-puts "您的 BMI 结果是: _________(过轻或正常或过重)"
+if c < 18.5
+  d = "过轻"
+elsif c >= 24
+  d = "过重"
+else d = "正常"
+
+end
+
+puts "您的 BMI 是: #{c}"
+
+puts "您的 BMI 结果是: #{d}"

06-interger-positive.rb

@@ -5,6 +5,24 @@
 x = gets
 
 # ....
+a = x.to_i
 
-puts "这个数是_____ (正数或零或负数)"
-puts "这个数是_____ (偶数或奇数)"
+if a > 0
+  b = "正数"
+elsif a == 0
+  b = "零"
+else b = "负数"
+
+end
+if a > 0
+
+if a % 2 == 0
+  c = "偶数"
+else
+  c = "奇数"
+end
+
+end
+
+puts "这个数是: #{b}"
+puts "这个数是: #{c}"

07-abcde.rb

@@ -11,6 +11,7 @@
 print "请输入一个整数x，然后按 Enter: "
 x = gets
 
+
 print "请输入一个整数y，然后按 Enter: "
 y = gets
 
@@ -19,4 +20,23 @@
 
 # ....
 
-puts "结果是________(A或B或C或D或E)"
+a = x.to_f
+b = y.to_f
+c = z.to_f
+
+if a < 0
+  h = "A"
+elsif a > 0 && b > 0 && c > 0
+  h = "B"
+  elsif a > 0 && b > 0 && c < 0
+    h = "C"
+  elsif a > 0 && b < 0 && c > 0
+    h = "D"
+  elsif a > 0 && b < 0 && c < 0
+    h = "E"
+end
+
+
+
+
+puts "结果是:#{h}"

08-find-max.rb

@@ -11,4 +11,21 @@
 
 # ....
 
-puts "最大的数是 ________(x或y或z)"
+x = x.to_f
+y = y.to_f
+z = z.to_f
+
+# if x > y && x > z
+#   h = "x"
+# elsif y > x && y > z
+#   h = "y"
+# elsif z > x && z > y
+#   h = "z"
+# else
+#   puts "无法求解"
+#
+# end
+
+h = [x, y, z].max.to_i
+
+puts "最大的数是: #{h}"

09-function.rb

@@ -1,15 +1,18 @@
 # 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)
-  # ....
+  a * b / 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}"
+puts "直角三角形的面积是: #{answer}"

10-function.rb

@@ -1,6 +1,7 @@
 # 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)
+  [x, y, z].max
 end
 
 print "请输入一个数字x，然后按 Enter: "
@@ -16,4 +17,4 @@ def find_max(x, y, z)
 
 answer = find_max(x,y,z)
 
-puts "最大的数是 #{answer}"
+puts "最大的数是 #{answer}"

11-seven.rb

@@ -2,8 +2,11 @@
 
 i = 1
 while ( i <= 100 )
+  if i % 7 == 0
+    puts i
+  end
 
   # ....
 
   i+=1
-end
+end

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
+puts total

13-nn.rb

@@ -1,11 +1,21 @@
 # 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
+n = gets.to_i
 
 # while ( ... )
 #   while ( ...)
 #
 #   end
 # end
+i = 0
+while (i <= n)
+  j = 0
+  while (j <= n)
+    h = i * j
+    puts "#{i} × #{j} = #{h}"
+    j += 1
+  end
 
+  i += 1
+end

14-prime.rb

@@ -2,6 +2,15 @@
 
 def is_prime(n)
 # ....
+  i = 2
+  while (i <= n/2)
+    if n % i == 0
+      return false
+    end
+    i += 1
+  end
+    return true
+
 end
 
 print "请输入数字 N，然后按 Enter: "

15-guess-number.rb

@@ -8,10 +8,14 @@
 
   #puts "太低了，再猜一次"
   #puts "太高了，再猜一次"
+  if n.to_i < target
+    puts "太低了，再猜一次"
+  elsif n.to_i > target
+    puts "太高了，再猜一次"
 
-  if n.to_i == target
+  else n.to_i == target
     puts "恭喜猜中啦! "
     break
   end
 
-end
+end

16-array-sum.rb

@@ -2,10 +2,16 @@
 
 def find_max(array)
   #....
+  # array.max
+  b = 0
+  array.each do |a|
+    if b < a
+      b = a
+    end
+  end
 end
 
 arr = [8, 12, 36, 53, 9, 75, 3, 71, 59, 88]
 
 max = find_max(arr)
 puts "Max is #{max}" # 应该是 88
-

17-array-stats.rb

@@ -12,9 +12,16 @@
   end
 end
 
+sum = 0
+arr.each { |i| sum += i}
+average = sum/arr.size.to_f
+
+
+
+
 puts arr.to_s
 
-puts "总和是 _____"
-puts "平均是 _____"
-puts "最大值是 _____"
-puts "最小值是 _____"
+puts "总和是 #{sum}"
+puts "平均是 #{average}"
+puts "最大值是 #{arr.max}"
+puts "最小值是 #{arr.min}"

18-square.rb

@@ -3,8 +3,17 @@
 arr = []
 
 print "请输入数字 N，然后按 Enter: "
-n = gets
+n = gets.to_i
 
 # ...
+# i = 0
+# while i < n
+#   arr << i * i
+#   i += 1
+# end
 
-puts arr.to_s
+(0..n).each_with_index do |i, j|
+  arr << j ** 2
+end
+
+puts arr.to_s

19-filter.rb

@@ -2,8 +2,16 @@
 
 def filter_even(arr)
   #...
+  new_array = []
+
+  arr.each do |i|
+    if i % 2 == 0
+      new_array << i
+    end
+  end
+  print "#{new_array}"
 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]
+puts filter_even(arr).to_s # 应该是 [68, 42, 46, 46, 86]

20-sorting.rb

@@ -2,10 +2,19 @@
 # Hint: 可用 arr.sort 排序，和 arr.uniq 去除重复
 
 def filter_even(arr)
-  #...
+  new_array = []
+
+  arr.each do |i|
+    if i % 2 == 0
+      new_array << i
+    end
+  end
+  print "#{new_array.sort.uniq}"
 end
 
+
+
 arr =  [7, 68, 42, 46, 9, 91, 77, 46, 86, 1]
 
 
-puts "________" # 应该是 [42, 46, 68, 86]
+puts "#{filter_even(arr)}" # 应该是 [42, 46, 68, 86]