Search, Insert, and Delete in an Sorted Array | Array Operations (original) (raw)

Last Updated : 14 Sep, 2024

**How to Search in a Sorted Array?

In a sorted array, the search operation can be performed by using binary search.

Below is the implementation of the above approach:

C++ `

// C++ program to implement binary search in sorted array #include <bits/stdc++.h> using namespace std;

int binarySearch(int arr[], int low, int high, int key) { if (high < low) return -1; int mid = (low + high) / 2; /*low + (high - low)/2;*/ if (key == arr[mid]) return mid; if (key > arr[mid]) return binarySearch(arr, (mid + 1), high, key); return binarySearch(arr, low, (mid - 1), key); }

/* Driver code */ int main() { // Let us search 3 in below array int arr[] = { 5, 6, 7, 8, 9, 10 }; int n, key;

n = sizeof(arr) / sizeof(arr[0]);
key = 10;

// Function call
cout << "Index: " << binarySearch(arr, 0, n - 1, key)
     << endl;
return 0;

}

// This code is contributed by NamrataSrivastava1

C

// C program to implement binary search in sorted array #include <stdio.h>

/* Driver Code */ int main() { // Let us search 3 in below array int arr[] = { 5, 6, 7, 8, 9, 10 }; int n, key;

n = sizeof(arr) / sizeof(arr[0]);
key = 10;

// Function call
printf("Index: %d\n", binarySearch(arr, 0, n - 1, key));
return 0;

}

Java

// Java program to implement binary // search in a sorted array

class Main { // function to implement // binary search static int binarySearch(int arr[], int low, int high, int key) { if (high < low) return -1;

    /*low + (high - low)/2;*/
    int mid = (low + high) / 2;
    if (key == arr[mid])
        return mid;
    if (key > arr[mid])
        return binarySearch(arr, (mid + 1), high, key);
    return binarySearch(arr, low, (mid - 1), key);
}

/* Driver Code*/
public static void main(String[] args)
{
    int arr[] = { 5, 6, 7, 8, 9, 10 };
    int n, key;
    n = arr.length - 1;
    key = 10;

    // Function call
    System.out.println("Index: "
                       + binarySearch(arr, 0, n, key));
}

}

Python3

python 3 program to implement

binary search in sorted array

def binarySearch(arr, low, high, key):

mid = (low + high)/2

if (key == arr[int(mid)]):
    return mid

if (key > arr[int(mid)]):
    return binarySearch(arr,
                        (mid + 1), high, key)

if (key < arr[int(mid)]):
    return binarySearch(arr, low, (mid-1), key)

return 0

Driver code

if name == "main": # Let us search 3 in below array arr = [5, 6, 7, 8, 9, 10] n = len(arr) key = 10

# Function call
print("Index:", int(binarySearch(arr, 0, n-1, key)))

This code is contributed by

Smitha Dinesh Semwal

C#

// C# program to implement binary // search in a sorted array

using System;

public class GFG {

// function to implement
// binary search
public static int binarySearch(int[] arr, int low,
                               int high, int key)
{
    if (high < low) {
        return -1;
    }

    int mid = (low + high) / 2;
    if (key == arr[mid]) {
        return mid;
    }
    if (key > arr[mid]) {
        return binarySearch(arr, (mid + 1), high, key);
    }
    return binarySearch(arr, low, (mid - 1), key);
}

/* Driver Code */
public static void Main(string[] args)
{
    int[] arr = new int[] { 5, 6, 7, 8, 9, 10 };
    int n, key;
    n = arr.Length;
    key = 10;

    // Function call
    Console.WriteLine(
        "Index: " + binarySearch(arr, 0, n - 1, key));
}

}

// This code is contributed by Shrikant13

JavaScript

PHP

high,high, high,key) { if ($high < $low) return -1; mid=(int)(mid = (int)(mid=(int)(low + $high) / 2; if ($key == arr[(int)arr[(int)arr[(int)mid]) return $mid; if ($key > arr[(int)arr[(int)arr[(int)mid]) return binarySearch($arr, ($mid + 1), high,high, high,key); return (binarySearch($arr, $low, ($mid -1), $key)); } // Driver Code // Let us search 3 in below array $arr = array(5, 6, 7, 8, 9, 10); n=count(n = count(n=count(arr); $key = 10; // Function call echo "Index: ", (int)binarySearch($arr, 0, n−1,n-1, n−1,key); // This code is contributed by // Srathore ?>

**Time Complexity: O(log(n)) Using Binary Search
**Auxiliary Space: O(log(n)) due to recursive calls, otherwise iterative version uses Auxiliary Space of O(1).

**How to Insert in a Sorted Array?

In a sorted array, a search operation is performed for the possible position of the given element by using Binary search, and then an insert operation is performed followed by shifting the elements. And in an unsorted array, the insert operation is faster as compared to the sorted array because we don’t have to care about the position at which the element is placed.

Insert Operation in sorted array

Below is the implementation of the above approach:

C++ `

// C++ program to implement insert operation in // an sorted array. #include <bits/stdc++.h> using namespace std;

// Inserts a key in arr[] of given capacity. n is current // size of arr[]. This function returns n+1 if insertion // is successful, else n. int insertSorted(int arr[], int n, int key, int capacity) { // Cannot insert more elements if n is already // more than or equal to capacity if (n >= capacity) return n;

int i;
for (i = n - 1; (i >= 0 && arr[i] > key); i--)
    arr[i + 1] = arr[i];

arr[i + 1] = key;

return (n + 1);

}

/* Driver code */ int main() { int arr[20] = { 12, 16, 20, 40, 50, 70 }; int capacity = sizeof(arr) / sizeof(arr[0]); int n = 6; int i, key = 26;

cout << "\nBefore Insertion: ";
for (i = 0; i < n; i++)
    cout << arr[i] << " ";

// Function call
n = insertSorted(arr, n, key, capacity);

cout << "\nAfter Insertion: ";
for (i = 0; i < n; i++)
    cout << arr[i] << " ";

return 0;

}

// This code is contributed by SHUBHAMSINGH10

C

// C program to implement insert operation in // an sorted array. #include <stdio.h>

int i;
for (i = n - 1; (i >= 0 && arr[i] > key); i--)
    arr[i + 1] = arr[i];

arr[i + 1] = key;

return (n + 1);

}

/* Driver code */ int main() { int arr[20] = { 12, 16, 20, 40, 50, 70 }; int capacity = sizeof(arr) / sizeof(arr[0]); int n = 6; int i, key = 26;

printf("\nBefore Insertion: ");
for (i = 0; i < n; i++)
    printf("%d  ", arr[i]);

// Function call
n = insertSorted(arr, n, key, capacity);

printf("\nAfter Insertion: ");
for (i = 0; i < n; i++)
    printf("%d  ", arr[i]);

return 0;

}

Java

// Java program to insert an // element in a sorted array

class Main { // Inserts a key in arr[] of given // capacity. n is current size of arr[]. // This function returns n+1 if insertion // is successful, else n. static int insertSorted(int arr[], int n, int key, int capacity) { // Cannot insert more elements if n is already // more than or equal to capacity if (n >= capacity) return n;

    int i;
    for (i = n - 1; (i >= 0 && arr[i] > key); i--)
        arr[i + 1] = arr[i];

    arr[i + 1] = key;

    return (n + 1);
}

/* Driver code */
public static void main(String[] args)
{
    int arr[] = new int[20];
    arr[0] = 12;
    arr[1] = 16;
    arr[2] = 20;
    arr[3] = 40;
    arr[4] = 50;
    arr[5] = 70;
    int capacity = arr.length;
    int n = 6;
    int key = 26;

    System.out.print("\nBefore Insertion: ");
    for (int i = 0; i < n; i++)
        System.out.print(arr[i] + " ");

    // Function call
    n = insertSorted(arr, n, key, capacity);

    System.out.print("\nAfter Insertion: ");
    for (int i = 0; i < n; i++)
        System.out.print(arr[i] + " ");
}

}

Python3

Python3 program to implement insert

operation in an sorted array.

Inserts a key in arr[] of given capacity.

n is current size of arr[]. This function

returns n+1 if insertion is successful, else n.

def insertSorted(arr, n, key, capacity):

# Cannot insert more elements if n is
# already more than or equal to capacity
if (n >= capacity):
    return n

i = n - 1
while i >= 0 and arr[i] > key:
    arr[i + 1] = arr[i]
    i -= 1

arr[i + 1] = key

return (n + 1)

Driver Code

if name == "main": arr = [12, 16, 20, 40, 50, 70]

for i in range(20):
    arr.append(0)

capacity = len(arr)
n = 6
key = 26

print("Before Insertion: ", end=" ")
for i in range(n):
    print(arr[i], end=" ")

# Function call
n = insertSorted(arr, n, key, capacity)

print("\nAfter Insertion: ", end="")
for i in range(n):
    print(arr[i], end=" ")

This code is contributed by Mohit Kumar

C#

using System;

// C# program to insert an // element in a sorted array

public class GFG {

// Inserts a key in arr[] of given
// capacity.  n is current size of arr[].
// This function returns n+1 if insertion
// is successful, else n.
public static int insertSorted(int[] arr, int n,
                               int key, int capacity)
{
    // Cannot insert more elements if n is already
    // more than or equal to capacity
    if (n >= capacity) {
        return n;
    }

    int i;
    for (i = n - 1; (i >= 0 && arr[i] > key); i--) {
        arr[i + 1] = arr[i];
    }

    arr[i + 1] = key;

    return (n + 1);
}

/* Driver code */
public static void Main(string[] args)
{
    int[] arr = new int[20];
    arr[0] = 12;
    arr[1] = 16;
    arr[2] = 20;
    arr[3] = 40;
    arr[4] = 50;
    arr[5] = 70;
    int capacity = arr.Length;
    int n = 6;
    int key = 26;

    Console.Write("\nBefore Insertion: ");
    for (int i = 0; i < n; i++) {
        Console.Write(arr[i] + " ");
    }

    // Function call
    n = insertSorted(arr, n, key, capacity);

    Console.Write("\nAfter Insertion: ");
    for (int i = 0; i < n; i++) {
        Console.Write(arr[i] + " ");
    }
}

}

// This code is contributed by Shrikant13

JavaScript

Output

Before Insertion: 12 16 20 40 50 70 After Insertion: 12 16 20 26 40 50 70

**Time Complexity: O(N) [In the worst case all elements may have to be moved]
**Auxiliary Space: O(1)

**How to Delete in a Sorted Array?

In the delete operation, the element to be deleted is searched using binary search, and then the delete operation is performed followed by shifting the elements.

Deleting 3 from the array

Performing delete operation

Below is the implementation of the above approach:

C++ `

// C++ program to implement delete operation in a // sorted array #include <bits/stdc++.h> using namespace std;

// To search a key to be deleted int binarySearch(int arr[], int low, int high, int key);

/* Function to delete an element */ int deleteElement(int arr[], int n, int key) { // Find position of element to be deleted int pos = binarySearch(arr, 0, n - 1, key);

if (pos == -1) {
    cout << "Element not found";
    return n;
}

// Deleting element
int i;
for (i = pos; i < n - 1; i++)
    arr[i] = arr[i + 1];

return n - 1;

}

int binarySearch(int arr[], int low, int high, int key) { if (high < low) return -1; int mid = (low + high) / 2; if (key == arr[mid]) return mid; if (key > arr[mid]) return binarySearch(arr, (mid + 1), high, key); return binarySearch(arr, low, (mid - 1), key); }

// Driver code int main() { int i; int arr[] = { 10, 20, 30, 40, 50 };

int n = sizeof(arr) / sizeof(arr[0]);
int key = 30;

cout << "Array before deletion\n";
for (i = 0; i < n; i++)
    cout << arr[i] << " ";

// Function call
n = deleteElement(arr, n, key);

cout << "\n\nArray after deletion\n";
for (i = 0; i < n; i++)
    cout << arr[i] << " ";

}

// This code is contributed by shubhamsingh10

C

// C program to implement delete operation in a // sorted array #include <stdio.h>

// To search a key to be deleted int binarySearch(int arr[], int low, int high, int key);

/* Function to delete an element */ int deleteElement(int arr[], int n, int key) { // Find position of element to be deleted int pos = binarySearch(arr, 0, n - 1, key);

if (pos == -1) {
    printf("Element not found");
    return n;
}

// Deleting element
int i;
for (i = pos; i < n - 1; i++)
    arr[i] = arr[i + 1];

return n - 1;

}

// Driver code int main() { int i; int arr[] = { 10, 20, 30, 40, 50 };

int n = sizeof(arr) / sizeof(arr[0]);
int key = 30;

printf("Array before deletion\n");
for (i = 0; i < n; i++)
    printf("%d  ", arr[i]);

// Function call
n = deleteElement(arr, n, key);

printf("\n\nArray after deletion\n");
for (i = 0; i < n; i++)
    printf("%d  ", arr[i]);

}

Java

// Java program to delete an // element from a sorted array

class Main {

// Binary search
static int binarySearch(int arr[], int low, int high,
                        int key)
{
    if (high < low)
        return -1;
    int mid = (low + high) / 2;
    if (key == arr[mid])
        return mid;
    if (key > arr[mid])
        return binarySearch(arr, (mid + 1), high, key);
    return binarySearch(arr, low, (mid - 1), key);
}

/* Function to delete an element */
static int deleteElement(int arr[], int n, int key)
{
    // Find position of element to be deleted
    int pos = binarySearch(arr, 0, n - 1, key);

    if (pos == -1) {
        System.out.println("Element not found");
        return n;
    }

    // Deleting element
    int i;
    for (i = pos; i < n - 1; i++)
        arr[i] = arr[i + 1];

    return n - 1;
}

/* Driver Code */
public static void main(String[] args)
{

    int i;
    int arr[] = { 10, 20, 30, 40, 50 };

    int n = arr.length;
    int key = 30;

    System.out.print("Array before deletion:\n");
    for (i = 0; i < n; i++)
        System.out.print(arr[i] + " ");

    // Function call
    n = deleteElement(arr, n, key);

    System.out.print("\n\nArray after deletion:\n");
    for (i = 0; i < n; i++)
        System.out.print(arr[i] + " ");
}

}

Python3

Python program to implement delete operation in a

sorted array

/* Function to delete an element */

def deleteElement(arr, n, key):

# Find position of element to be deleted
pos = binarySearch(arr, 0, n - 1, key)

if (pos == -1):
    print("Element not found")
    return n

# Deleting element
for i in range(pos, n - 1):
    arr[i] = arr[i + 1]

return n - 1

To search a key to be deleted

def binarySearch(arr, low, high, key):

if (high < low):
    return -1
mid = (low + high) // 2

if (key == arr[mid]):
    return mid
if (key > arr[mid]):
    return binarySearch(arr, (mid + 1), high, key)

return binarySearch(arr, low, (mid - 1), key)

Driver code

if name == "main": arr = [10, 20, 30, 40, 50]

n = len(arr)
key = 30

print("Array before deletion")

for i in range(n):
    print(arr[i], end=" ")

# Function call
n = deleteElement(arr, n, key)
print("\n\nArray after deletion")
for i in range(n):
    print(arr[i], end=" ")

This code is contributed by shubhamsingh10

C#

// C# program to delete an // element from a sorted array using System; public class GFG {

// Binary search
static int binarySearch(int[] arr, int low, int high,
                        int key)
{
    if (high < low)
        return -1;
    int mid = (low + high) / 2;
    if (key == arr[mid])
        return mid;
    if (key > arr[mid])
        return binarySearch(arr, (mid + 1), high, key);
    return binarySearch(arr, low, (mid - 1), key);
}

/* Function to delete an element */
static int deleteElement(int[] arr, int n, int key)
{
    // Find position of element to be deleted
    int pos = binarySearch(arr, 0, n - 1, key);

    if (pos == -1) {
        Console.WriteLine("Element not found");
        return n;
    }

    // Deleting element
    int i;
    for (i = pos; i < n - 1; i++)
        arr[i] = arr[i + 1];

    return n - 1;
}

/* Driver Code */
public static void Main()
{

    int i;
    int[] arr = { 10, 20, 30, 40, 50 };

    int n = arr.Length;
    int key = 30;

    Console.Write("Array before deletion:\n");
    for (i = 0; i < n; i++)
        Console.Write(arr[i] + " ");

    // Function call
    n = deleteElement(arr, n, key);

    Console.Write("\n\nArray after deletion:\n");
    for (i = 0; i < n; i++)
        Console.Write(arr[i] + " ");
}

}

// This code is contributed by Rajput-Ji

JavaScript

Output

Array before deletion 10 20 30 40 50

Array after deletion 10 20 40 50

**Time Complexity: O(N). In the worst case all elements may have to be moved
**Auxiliary Space: O(log N). An implicit stack will be used