Question

我正在尝试执行一个程序，一次向用户询问三个数字，将它们存储在数组中，然后打印数字列表和总数。

请解释。

这是我到目前为止所做的：

numbers = Array.new
numbers = []
puts "Enter first number: "
first = gets.to_i
puts "Enter second number: "
second = gets.to_i
puts "Enter third number: "
third = gets.to_i
def sum(numbers)
  return 0 if numbers.length < 1
  result = 0
  numbers.each { |num| result += num }
  result
end

Answer 1

您也可以使用Array的reduce方法。

http://ruby-doc.org/core-2.1.0/Enumerable.html#method-i-reduce

#!/usr/bin/ruby
numbers = Array.new
# numbers = [] #this is same as above
puts "Enter first number: "
first = gets.to_i
numbers<<first
puts "Enter second number: "
second = gets.to_i
numbers<<second
puts "Enter third number: "
third = gets.to_i
numbers<<third
puts numbers.reduce {|sum, n| sum + n } #here

Answer 2

这是另外一种方法：

long minutes = TimeUnit.MILLISECONDS.toMinutes(a - b);

也可以写成如下：

sum = 3.times.collect{ |i| puts "Enter number #{i + 1}:"; gets.chomp.to_i }.inject(:+)
puts sum

Answer 3

您没有将任何输入推入阵列，您可以使用推送功能或＆lt;＆lt;向元素中添加元素

  #!/usr/bin/ruby
numbers = Array.new
numbers = []
puts "Enter first number: "
first = gets.to_i
numbers<<first
puts "Enter second number: "
second = gets.to_i
numbers<<second
puts "Enter third number: "
third = gets.to_i
numbers<<first
def sum(someArray)
  return 0 if someArray.length < 1
  result = 0
  someArray.each { |num| result += num }
  result
end

希望有所帮助

Answer 4

这里有两个问题：

您没有将您阅读的数字推入数组
您正确定义了sum功能，但未在任何地方调用

#!/usr/bin/ruby
numbers = Array.new # note the second, redundant, initialization on numbers was removed
puts "Enter first number: "
(numbers ||= []) << gets.to_i # Pushing read value into the array (issue 1)
puts "Enter second number: "
(numbers ||= []) << gets.to_i # Here too
puts "Enter third number: "
(numbers ||= []) << gets.to_i # And here too
def sum(numbers)
  return 0 if numbers.length < 1
  result = 0
  numbers.each { |num| result += num }
  result
end

puts sum(numbers) # Calling sum (issue 2)

在Ruby数组中求和

4 个答案: