go语言数组与切片

package array_test
 
import "testing"
 
//数组
func TestArrayInit(t *testing.T) {
  //默认初始化零值
  var arr [3]int
  //初始化并赋值
  arr1 := [4]int{1, 2, 3, 4}
  //初始化，自动获取数组长度
  arr2 := [...]int{1, 2, 3, 4}
  t.Log(arr[0], arr[1])
  t.Log(arr1, arr2)
  //  数组遍历
  for i := 0; i < len(arr2); i++ {
    t.Log(arr2[i])
  }
  //range遍历
  for i, e := range arr2 {
    t.Log(i, e)
  }
  //  range遍历 使用占位
  for i, _ := range arr2 {
    t.Log(i)
  }
  //  多维数组申明
  arr3 := [2][2]int{{1, 2}, {1, 2}}
  t.Log(arr3)
  //  数组截取[开始（包含）,结束(不包含)] 使用len不会越界
  arr4 := [...]int{1, 2, 3, 4, 5}
  t.Log(arr4[1:2]) //2
  t.Log(arr4[1:])  //2 3 4 5
  t.Log(arr4[:2])  //1 2
}
 
//  数组可比较，维数、顺序、值相同 true
func TestArrayComparing(t *testing.T) {
  a := [...]int{1, 2, 3, 4}
  b := [...]int{1, 2, 3, 4}
  t.Log(a == b)
}

package slice_test
 
import "testing"
 
//切片
func TestSlice(t *testing.T) {
  //  申明
  var s0 []int
  t.Log(len(s0), cap(s0))
  s0 = append(s0, 50)
  t.Log(len(s0), cap(s0))
  //申明并初始化
  s1 := []int{1, 2, 3, 4}
  t.Log(len(s1), cap(s1))
  //使用make初始化
  s2 := make([]int, 3, 5)
  t.Log("初始化", len(s2), cap(s2))
  s2 = append(s2, 6)
  t.Log(s2[0], s2[1], s2[2], s2[3])
  t.Log("添加元素后：", len(s2), cap(s2))
}
 
//切片扩容，翻倍
func TestSliceGrowing(t *testing.T) {
  s := []int{}
  for i := 0; i < 10; i++ {
    //地址可能发生变化，重新赋值
    s = append(s, i)
    t.Log(len(s), cap(s))
 
  }
}
 
//共享切片
func TestSliceShareMemory(t *testing.T) {
  //初始化
  year := []string{"Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "sep", "Oct", "Nov", "Dec"}
  t.Log("year", len(year), cap(year))
  //切片1
  q2 := year[3:6]
  t.Log(q2, len(q2), cap(q2))
  //切片2
  summer := year[5:8]
  t.Log(summer, len(summer), cap(summer))
  summer[0] = "Unknow"
  t.Log(q2)
  t.Log(year)
}
 
//切片比较
func TestSliceComparing(t *testing.T) {
  a := []int{1, 2, 3, 4}
  b := []int{1, 2, 3, 4}
  t.Log(a, b)
  //t.Log(a == b)
}