红宝石 |数组移位()函数
Array#shift() : shift()是一个 Array 类方法,它删除 self 的第一个元素并返回它,如果数组为空则返回 nil。
Syntax: Array.shift()
Parameter: Array
Return: removes the first element of self and returns it or nil if the array is empty.
示例 #1:
# Ruby code for shift() method
# declaring array
a = [18, 22, 33, nil, 5, 6]
# declaring array
b = [1, 4, 1, 1, 88, 9]
# declaring array
c = [18, 22, 50, 6]
# shift method example
puts "shift() method form : #{a.shift()}\n\n"
puts "shift() method form : #{b.shift(2)}\n\n"
puts "shift() method form : #{c.shift(3)}\n\n"
输出 :
shift() method form : 18
shift() method form : [1, 4]
shift() method form : [18, 22, 50]
示例 #2:
# Ruby code for shift() method
# declaring array
a = ["abc", "nil", "dog"]
# declaring array
c = ["cat", nil]
# declaring array
b = ["cow", nil, "dog"]
# shift method example
puts "shift() method form : #{a.shift()}\n\n"
puts "shift() method form : #{b.shift()}\n\n"
puts "shift() method form : #{c.shift()}\n\n"
输出 :
shift() method form : abc
shift() method form : cow
shift() method form : cat