How to delete an element from a Slice in Golang

Question

fmt.Println(\"Enter position to delete::\")
fmt.Scanln(&pos)

new_arr := make([]int, (len(arr) - 1))
k := 0
for i := 0; i < (len(arr) - 1); {
    if i != pos {
           


        

Answer 1

The best way to do it is to use the append function:

package main

import (
    "fmt"
)

func main() {
    x := []int{4, 5, 6, 7, 88}
    fmt.Println(x)
    x = append(x[:2], x[4:]...)//deletes 6 and 7
    fmt.Println(x)
}

https://play.golang.org/p/-EEFCsqse4u

Answer 2

Minor point (code golf), but in the case where order does not matter you don't need to swap the values. Just overwrite the array position being removed with a duplicate of the last position and then return a truncated array.

func remove(s []int, i int) []int {
    s[i] = s[len(s)-1]
    return s[:len(s)-1]
}

Same result.

Answer 3

Maybe this code will help.

It deletes item with a given index.

Takes the array, and the index to delete and returns a new array pretty much like append function.

func deleteItem(arr []int, index int) []int{
  if index < 0 || index >= len(arr){
    return []int{-1}
  }

    for i := index; i < len(arr) -1; i++{
      arr[i] = arr[i + 1]

    }

    return arr[:len(arr)-1]
}

Here you can play with the code : https://play.golang.org/p/aX1Qj40uTVs

Answer 4

To remove an element from the middle of a slice, preserving the order of the remaining elements, use copy to slide the higher-numbered elements down by one to fill the gap:

func remove(slice []int, i int) []int {
  copy(slice[i:], slice[i+1:])
  return slice[:len(slice)-1]
}

If it is not necessary to preserve the order, we can simply move the last element to the gap.

func remove(slice []int, i int) []int {
  slice[i] = slice[len(slice)-1]
  return slice[:len(slice)-1]
}

Answer 5

Remove one element from the Slice (this is called 're-slicing'):

package main

import (
    "fmt"
)

func RemoveIndex(s []int, index int) []int {
    return append(s[:index], s[index+1:]...)
}

func main() {
    all := []int{0, 1, 2, 3, 4, 5, 6, 7, 8, 9}
    fmt.Println(all) //[0 1 2 3 4 5 6 7 8 9]
    all = RemoveIndex(all, 5)
    fmt.Println(all) //[0 1 2 3 4 6 7 8 9]
}

Answer 6

This is how you Delete From a slice the idiomatic way. You don't need to build a function it is built into the append. Try it here https://play.golang.org/p/QMXn9-6gU5P

z := []int{9, 8, 7, 6, 5, 3, 2, 1, 0}
fmt.Println(z)  //will print Answer [9 8 7 6 5 3 2 1 0]

z = append(z[:2], z[4:]...)
fmt.Println(z)   //will print Answer [9 8 5 3 2 1 0]