go slice


原文链接: go slice
   var numbers = make([]int)     // len 0 cap 0 
   var numbers = make([]int,5)   // len 5 cap 5
   var numbers = make([]int,3,5) // len 3 cap 5

对切片的各类操作,如去重Distinct,求交集InnerJoin,合集FullJoin等

func DeleteSlice(a []int) []int{

for i := 0; i < len(a); i++ {
    if a[i] == 0 {
        a = append(a[:i], a[i+1:]...)
        i--
    }
}
return a

}
1、基本用法:

a = append(a, b...)
例如:list = appened(list,[]int{1,2,3,4}...)
可以用来合并两个列表. 不用这样了 :list := make([]int,len(list1)+len(list2)) 然后再copy(list,list1) copy(list[len(list1):],list2)

2、Copy:

b = make([]T, len(a)) copy(b, a)

或者:

b = append([]T(nil), a...)

3、Cut:

a = append(a[:i], a[j:]...)

4、Delete:

a = append(a[:i], a[i+1:]...)
或者: a = a[:i+copy(a[i:], a[i+1:])]
例如:a[len(a)-1], a = nil, append(a[:i], a[i+1:]...)

5、Delete without preserving order:

a[i], a = a[len(a)-1], a[:len(a)-1]
例如: a[i], a[len(a)-1], a = a[len(a)-1], nil, a[:len(a)-1]

6、Expand:

a = append(a[:i], append(make([]T, j), a[i:]...)...)

7、Extend:

a = append(a, make([]T, j)...)

8、Insert:

a = append(a[:i], append([]T{x}, a[i:]...)...)
例如: s = append(s, 0) copy(s[i+1:], s[i:]) s[i] = x

9、InsertVector:

a = append(a[:i], append(b, a[i:]...)...)

10、Pop

x, a = a[len(a)-1], a[:len(a)-1]

11、Push:

a = append(a, x)

12、Shift

x, a := a[0], a[1:]

13、Unshift

a = append([]T{x}, a...)

14、Reversing:

for i := len(a)/2-1; i >= 0; i-- { 
   opp := len(a)-1-i a[i], a[opp] = a[opp], a[i]
}
for left, right := 0, len(a)-1; left < right; left, right = left+1, right-1 {
a[left], a[right] = a[right], a[left]

}

`