Swift – 集合和数组的区别
数组是具有连续内存的线性数据结构。在单个变量中,我们可以存储 n 个元素。例如,如果我们想从用户那里获取 10 个输入,我们就不能初始化 10 个变量。为此,我们可以使用数组。它可以将 n 个元素存储到单个变量中。可以使用索引访问元素。
句法:
var arr:[Int] = [value 1 , value 2 , value 3, . . . . value n]
例子:
Swift
// Swift program to illustrate array
// Creating and initializing array
var arr:[Int] = [ 1, 2, 3, 4, 5 ]
// Display the array
print(arr)
Swift
// Swift program to illustrate set
// Creating and initializing set
var set1:Set = [ 1, 2, 2, 2, 3, 4 ]
// Display the result
print(set1)
输出:
[1, 2, 3, 4, 5]
Set是一种不存在重复元素的数据结构。一般来说,在数组中,我们可以存储重复的元素,但是我们不能在集合中存储重复的元素。默认情况下,它会消除重复元素。就像在数学中一样,我们可以执行集合运算,例如并集、交集、集差等。
句法:
var set_variable : Set=[value 1, value 2 , . . . . value n]
例子:
迅速
// Swift program to illustrate set
// Creating and initializing set
var set1:Set = [ 1, 2, 2, 2, 3, 4 ]
// Display the result
print(set1)
输出 :
[2, 4, 1, 3]
注意:这里我们在创建集合时采用了重复的元素,但是在输出中,我们可以看到没有重复。由于该集合不允许重复。每次打印集合时,元素的顺序可能会发生变化。
数组和集合的区别
Array | Set |
---|---|
Array is faster than set in terms of initialization. | Set is slower than an array in terms of initialization because it uses a hash process. |
Parentheses ( ) are used to create arrays in swift | Square braces [ ] are used to create set in swift |
The array allows to store duplicate elements in it. | Set doesn’t allow to store duplicate elements in it. |
Elements in the array are arranged in order. Or we can say that arrays are ordered. | Elements in the set are not arranged in any specified order Or we can say that sets are unordered. |
Performance is not the main concern. | Performance plays an important. |