Ruby笔记四（数组） - Chinaunix

#E8.1-1.rb
=begin
数组的索引从0开始，一直到数组的长度减去1；
负数表示从数组末尾开始的索引；
用一对数字来索引数组，第一个数字表示开始位置，第二数字表示从开始位置起的元素数目
=end
arr=[3,4,5,6,7,8,9]
puts arr[0] #3
puts arr.first #3
puts arr[arr.length-1] #9
puts arr[arr.size-1] #9
puts arr.last #9
puts arr[-1] #9
puts arr[-2] #8
print arr[1..3].join(",") ,"\n" #4, 5, 6
print arr[-3,2] ,"\n" #[7, 8]
#Ruby的数组大小是动态的，你能够随时增加、删除数组元素。
arr=[4,5,6]
print arr.join(", "),"\n" #4, 5, 6
arr[4] = "m" #把4号索引位置元素赋值为"m"
print arr.join(", "),"\n" #4, 5, 6, , m
print arr[3] ,"\n" #打印3号索引位置元素 #nil
arr.delete_at(3) #删除3号索引位置元素
print arr.join(", "),"\n" #4, 5, 6, m
arr[2] = ["a","b","c"] #把2号索引位置元素赋值为["a","b","c"]
print arr.join(", "),"\n" #4, 5, a, b, c, m
print arr[2].join(",") ,"\n" #打印2号索引位置元素 #a,b,c
arr[0..1] = [7,"h","b"] #把0..1号元素替换为7,"h","b"
print arr.join(", "),"\n" #7, h, b, a, b, c, m
arr.push("b" ) #加入元素"b"
print arr.join(", "),"\n" #7, h, b, a, b, c, m, b
arr.delete(["a","b","c"] ) #删除元素["a","b","c"]
print arr.join(", "),"\n" #7, h, b, m, b
arr.delete("b") #删除所有元素"b"
print arr.join(", "),"\n" #7, h, m
arr.insert(3,"d") #在3号索引位置插入元素"d"
print arr.join(", "),"\n" #7, h, m, d
arr<<"f"<<2 #加入元素"f"；加入元素2
print arr.join(", "),"\n" #7, h, m, d, f, 2
arr.pop #删除尾元素
print arr.join(", "),"\n" #7, h, m, d, f
arr.shift #删除首元素
print arr.join(", "),"\n" #h, m, d, f
arr.clear #清空数组arr
print arr.join(", "),"\n" #
#数组运算
aaaa=["aa",4,5,"bb"]
bbbb=[4,1,3,2,5]
print (aaaa + bbbb).join(" ") ,"\n" #aa 4 5 bb 4 1 3 2 5
print (aaaa * 2).join(" ") ,"\n" #aa 4 5 bb aa 4 5 bb
print (bbbb - aaaa).join(" ") ,"\n" #1 3 2
#并运算；交运算
print (aaaa | bbbb).join(",") ,"\n" #aa,4,5,bb,1,3,2
print (aaaa & bbbb).join(",") ,"\n" #4,5
#排序；倒置
print bbbb.sort().join(",") ,"\n" #1,2,3,4,5
print aaaa.reverse.join(",") ,"\n" #bb,5,4,aa
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