Smallest subarray such that all elements are greater than K

Given an array of N integers and a number K, the task is to find the length of the smallest subarray in which all the elements are greater than K. If there is no such subarray possible, then print -1. 

Examples:

Input: a[] = {3, 4, 5, 6, 7, 2, 10, 11}, K = 5 
Output: 1 
The subarray is {10}

Input: a[] = {1, 2, 3}, K = 13 
Output: -1 

Approach: The task is to find the smallest subarray with all elements greater than K. Since smallest subarray can be of size 1. So, just check if there exists any element in the array greater than K. If yes then print “1” else print “-1”.

Below is the implementation of the above approach: 

C++

// C++ program to print the length of the shortest
// subarray with all elements greater than X
#include <bits/stdc++.h>
using namespace std;

// Function to return shortest array
int smallestSubarray(int a[], int n, int x)
{
    int count = 0, length = 0;

    // Iterate in the array
    for (int i = 0; i < n; i++) {

        // check if array element
        // greater than X or not
        if (a[i] > x) {
            return 1;
        }
    }

    return -1;
}

// Driver Code
int main()
{
    int a[] = { 1, 22, 3 };
    int n = sizeof(a) / sizeof(a[0]);
    int k = 13;

    cout << smallestSubarray(a, n, k);

    return 0;
}

Java

//  Java program to print the length of the shortest
// subarray with all elements greater than X

import java.io.*;

class GFG {

// Function to return shortest array
static int smallestSubarray(int a[], int n, int x)
{
    int count = 0, length = 0;

    // Iterate in the array
    for (int i = 0; i < n; i++) {

        // check if array element
        // greater than X or not
        if (a[i] > x) {
            return 1;
        }
    }

    return -1;
}

// Driver Code
    public static void main (String[] args) {
    int a[] = { 1, 22, 3 };
    int n = a.length;
    int k = 13;

    System.out.println(smallestSubarray(a, n, k));
            }
}
// This code has been contributed by anuj_67..

Python3

# Python 3 program to print the
# length of the shortest subarray
# with all elements greater than X

# Function to return shortest array
def smallestSubarray(a, n, k):

    # Iterate in the array
    for i in range(n):

        # check if array element
        # greater than X or not
        if a[i] > k:
            return 1
    return -1

# Driver Code
a = [1, 22, 3]
n = len(a)
k = 13
print(smallestSubarray(a, n, k))

# This code is contributed
# by Shrikant13

C#

using System;

class GFG
{

// Function to return shortest array
static int smallestSubarray(int []a,
                            int n, int x)
{

    // Iterate in the array
    for (int i = 0; i < n; i++)
    {

        // check if array element
        // greater than X or not
        if (a[i] > x)
        {
            return 1;
        }
    }

    return -1;
}

// Driver Code
static public void Main ()
{
    int []a = { 1, 22, 3 };
    int n = a.Length;
    int k = 13;

    Console.WriteLine(smallestSubarray(a, n, k));
}
}

// This code is contributed by ajit

PHP

<?php
// PHP program to print the length
// of the shortest subarray with
// all elements greater than X

// Function to return shortest array
function smallestSubarray($a, $n, $x)
{
    $count = 0;
    $length = 0;

    // Iterate in the array
    for ($i = 0; $i < $n; $i++)
    {

        // check if array element
        // greater than X or not
        if ($a[$i] > $x)
        {
            return 1;
        }
    }

    return -1;
}

// Driver Code
$a = array( 1, 22, 3 );
$n = sizeof($a);
$k = 13;

echo smallestSubarray($a, $n, $k);

// This code is contributed by ajit
?>

Javascript

<script>
// JavaScriptto print the length of the shortest
// subarray with all elements greater than X

// Function to return shortest array
function smallestSubarray(a, n, x)
{
    let count = 0, length = 0;

    // Iterate in the array
    for (let i = 0; i < n; i++) {

        // check if array element
        // greater than X or not
        if (a[i] > x) {
            return 1;
        }
    }

    return -1;
}

// Driver Code

    let a = [1, 22, 3 ]
    let n = a.length
    let k = 13;

    document.write(smallestSubarray(a, n, k));

// This code is contributed by Surbhi Tyagi.
</script>

Output

1

Complexity Analysis:

• Time Complexity: O(N) 
• Auxiliary Space: O(1)