Go (day3[array])

array: var variable name [Len]type

Usage scenarios:

• Fixed requirement, use array, cannot exceed specified length

• Length is also part of the array type

• The underlying memory space is contiguous

• Used to store constants

• Arrays are a special kind of dictionary .....

• Array write, assignment method, array [index]= value

• An array is a value type, and if you copy it into another array, the array is modified, and the original array does not change
  

Array initialization:

???? Defined:???? var variable name [Len]type

• The first kind:?

  • Var?a[5]?int?=? [5]int{1,2,3,4,5}

• The second type:

  • ceshi?:=[5]int{1,3,4,5}

• Third Kind

  • Var?b?=? [5]int{1,3}

• The fourth type (when the unknown length is used ...), it is important to note that this usage is also in the slice, but the meaning is different

  • Var?c?=? [...] int{1,3,4,5,10}

?

Example:

Var?a[5]intvar?a[5]stringvar?a[5]float32var?a[5]bool

To access an element in an array:

? Using subscript access:? A[0] accesses the first element. An array of length 5 is accessed as follows: A[0], a[1], a[2], a[3], a[4]

The length in the array:

???? var a[10]int

???? Lengh: =len (a)

The sample code splits the section:

2. Array loop:

   1. format%p, used to print memory address

   2. & symbol, take variable address

   3. Try using variables to loop

   4. var?a?[ 10]intfor?i?:=0;i<len (a); i++{??? Fmt. Printf ("%p\n", &a[i])} 

   5. length:=len (a)? Array length 

      
      

4. Array initialization:

   2. Creates another array, modifies the array, and does not modify the original array

   3. func?test2 ()?? {??? Var?a[5]int?? =? [5]int? {1,2,3,4,5}??? Var?b[5]?int??? B?=?a??? Fmt. Printf ("%v\n", b)??? B[0]?=?200??? Fmt. Printf ("%v\n", b)??? Fmt. Printf ("%v\n", a)} 

6. Array definition:

   1. when declaring an array, you need to define the length and type!!!

   2. array Assignment: Specify subscript to specify element assignment

   3. % #以go的方式打印

   4. var?d?[ 5]string?=? [5]string{1: "ABC", 4: "Zcq"}//%#?? Print to go!!! Fmt. Printf ("%#%v\n", D) fmt. Printf ("%v\n", a,b,c) 

8. Two-dimensional array

   1. func?test4 ()?? {??? Two-dimensional array??? Var?a[4][2]int??? for?i:=0;i<4;i++{?????? for?j:=0;i<2;j++{????????? A[i][i]?=? (i+1)? * (j+1)??????}???}??? for?i:=0;i<4;i++{?????? for?j:=0;i<2;j++{????????? Fmt. Printf ("%d", a[i][j])??????}?????? Fmt. Println ()???}}

10. Array Assignment: Random numbers into the array

    1. Remember: Go is a strongly typed language, so if the type is different, it is not compiled

    2. using the random number module, use the time module

       1. r?: =?rand. New (Rand. Newsource (time. Now (). Unix ()) 

    3. func?test5 ()?? {??? Random numbers into the array??? R?:=?rand. New (Rand. Newsource (time. Now (). Unix ()))??? Var?five? [100]int??? Array? To assign a value by index??? For?i:=0;i<len (five); i++{?????? Assignment Operation?????? Five[i]=r.int ()?????? Value Operation?????? Fmt. Printf ("%d\n", Five[i])???}??? Fmt. Printf ("%d\n", Five)} 

12. Array assignment: Random string into array

    1. Go inside is utf-8 code

    2. Sprintf format and return the formatted string, can be directly assigned value!!!

    3. Func?test6 ()?? {?????? Var?a? [100]string??? Var?b?string?=? " Abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz "??? For?i:=0;i<len (a); i++{?????? Var?str?string?????? For?j:=0;j<len (b); j++{????????? Index?:=rand. INTN (len (b))????????? Sprintf? format and return the formatted string????????? Str?=?fmt. Sprintf ("%s%c", Str,b[index])??????}?????? A[i]?=?str?????? Fmt. Printf ("a[%d]=%s\n", I,a[i])???}}

Go (day3[array])