Delete an Element from a Given Position in an Array (original) (raw)
Last Updated : 08 Nov, 2024
Given an array of integers, the task is to delete an element from a **given position in the array.
**Examples:
**Input: arr[] = [10, 20, 30, 40], pos = 1
**Output: [20, 30, 40]**Input: arr[] = [10, 20, 30, 40], pos = 2
**Output: [10, 30, 40]**Input: arr[] = [10, 20, 30, 40], pos = 4
**Output: [10, 20, 30]
Table of Content
[Approach 1] Using Built-In Methods
We will use library methods like **erase() in C++, **remove() in Java, **del in Python, **removeAt() in C# and **splice() in JavaScript.
C++ `
// C++ program to delete an element from a given
// position in an array
#include #include using namespace std;
int main() { vector arr = { 10, 20, 30, 40 }; int pos = 2;
cout << "Array before deletion\n";
for (int i = 0; i < arr.size(); i++)
cout << arr[i] << " ";
// Delete the element at the given position
arr.erase(arr.begin() + pos - 1);
cout << "\nArray after deletion\n";
for (int i = 0; i < arr.size(); i++)
cout << arr[i] << " ";
return 0;}
Java
// Java program to delete an element from a given
// position of an array
import java.util.*;
class GfG { public static void main(String[] args) { ArrayList arr = new ArrayList (Arrays.asList(10, 20, 30, 40)); int pos = 2;
System.out.println("Array before deletion");
for (int i = 0; i < arr.size(); i++)
System.out.print(arr.get(i) + " ");
// Delete the element at the specified position
arr.remove(pos - 1);
System.out.println("\nArray after deletion");
for (int i = 0; i < arr.size(); i++)
System.out.print(arr.get(i) + " ");
}}
Python
Python program to delete an element from a given
position of an array
arr = [10, 20, 30, 40] pos = 2
print("Array before deletion") for num in arr: print(num, end=" ")
Delete the element at the specified position
del arr[pos - 1]
print("\nArray after deletion") for num in arr: print(num, end=" ")
C#
// C# program to delete an element from a given
// position of an array
using System; using System.Collections.Generic;
class GfG { static void Main() { List arr = new List { 10, 20, 30, 40 }; int pos = 2;
Console.WriteLine("Array before deletion");
foreach (int num in arr)
Console.Write(num + " ");
// Delete the element at the specified position
arr.RemoveAt(pos - 1);
Console.WriteLine("\nArray after deletion");
foreach (int num in arr)
Console.Write(num + " ");
}}
JavaScript
// JavaScript program to delete an element from a given
// position of an array
let arr = [10, 20, 30, 40]; let pos = 2;
console.log("Array before deletion"); console.log(arr)
// Delete the element at the specified position arr.splice(pos - 1, 1);
console.log("Array after deletion"); console.log(arr);
`
Output
Array before deletion 10 20 30 40 Array after deletion 10 30 40
**Time Complexity: O(n), where **n is the size of array.
**Auxiliary Space: O(1)
[Approach 2] Using Custom Method
The idea is to shift all the elements occurring after the given position, one index to the left and reduce the size of the array by 1.
C++ `
// C++ program to delete an element from a given
// position in an array using custom method
#include #include using namespace std;
int main() { vector arr = { 10, 20, 30, 40 }; int n = arr.size(); int pos = 2;
cout << "Array before deletion\n";
for (int i = 0; i < n; i++)
cout << arr[i] << " ";
// Delete the element at the given position
for(int i = pos; i < n; i++) {
arr[i - 1] = arr[i];
}
if(pos <= n)
n--;
cout << "\nArray after deletion\n";
for (int i = 0; i < n; i++)
cout << arr[i] << " ";
return 0;}
C
// C program to delete an element from a given
// position in an array using custom method
#include <stdio.h>
int main() { int arr[] = { 10, 20, 30, 40 }; int n = sizeof(arr)/sizeof(arr[0]); int pos = 2;
printf("Array before deletion\n");
for (int i = 0; i < n; i++) {
printf("%d ", arr[i]);
}
// Delete the element at the given position
for (int i = pos; i < n; i++) {
arr[i - 1] = arr[i];
}
if (pos <= n)
n--;
printf("\nArray after deletion\n");
for (int i = 0; i < n; i++) {
printf("%d ", arr[i]);
}
return 0;}
Java
// Java program to delete an element from a given
// position in an array using custom method
class GfG { public static void main(String[] args) { int[] arr = { 10, 20, 30, 40 }; int n = arr.length; int pos = 2;
System.out.println("Array before deletion");
for (int i = 0; i < n; i++) {
System.out.print(arr[i] + " ");
}
// Delete the element at the given position
for (int i = pos; i < n; i++) {
arr[i - 1] = arr[i];
}
if (pos <= n) {
n--;
}
System.out.println("\nArray after deletion");
for (int i = 0; i < n; i++) {
System.out.print(arr[i] + " ");
}
}}
Python
Python program to delete an element from a given
position in an array using custom method
if name == "main": arr = [10, 20, 30, 40] n = len(arr) pos = 2
print("Array before deletion")
for i in range(n):
print(arr[i], end=" ")
# Delete the element at the given position
for i in range(pos, n):
arr[i - 1] = arr[i]
if pos <= n:
n -= 1
print("\nArray after deletion")
for i in range(n):
print(arr[i], end=" ")C#
// C# program to delete an element from a given
// position in an array using custom method
using System;
class GfG { static void Main() { int[] arr = { 10, 20, 30, 40 }; int n = arr.Length; int pos = 2;
Console.WriteLine("Array before deletion");
for (int i = 0; i < n; i++) {
Console.Write(arr[i] + " ");
}
// Delete the element at the given position
for (int i = pos; i < n; i++) {
arr[i - 1] = arr[i];
}
if (pos <= n)
n--;
Console.WriteLine("\nArray after deletion");
for (int i = 0; i < n; i++) {
Console.Write(arr[i] + " ");
}
}}
JavaScript
// JavaScript program to delete an element from a given // position in an array using custom method
let arr = [ 10, 20, 30, 40 ]; let pos = 2; let n = arr.length;
console.log("Array before deletion"); for (let i = 0; i < n; i++) { console.log(arr[i]); }
// Delete the element at the given position for (let i = pos; i < n; i++) { arr[i - 1] = arr[i]; }
if (pos <= n) { n--; }
console.log("\nArray after deletion"); for (let i = 0; i < n; i++) { console.log(arr[i]); }
`
Output
Array before deletion 10 20 30 40 Array after deletion 10 30 40
**Time Complexity: O(n), where **n is the size of array.
**Auxiliary Space: O(1)