# Greatest contiguous sub-array of size K

Given an array arr[] of integers and an integer K, the task is to find the greatest contiguous sub-array of size K. Sub-array X is said to be greater than sub-array Y if the first non-matching element in both the sub-arrays has a greater value in X than in Y.

Examples:

Input: arr[] = {1, 4, 3, 2, 5}, K = 4
Output: 4 3 2 5
Two subarrays are {1, 4, 3, 2} and {4, 3, 2, 5}.
Hence, the greater one is {4, 3, 2, 5}

Input: arr[] = {1, 9, 2, 7, 9, 3}, K = 3
Output: 9 2 7

## Recommended: Please try your approach on {IDE} first, before moving on to the solution.

Approach: Generate all the sub-arrays of size K and store them in any Data-Structure. Sort all the sub-arrays, and the answer will be the last sub-array in the sorted Data-structure. In C++, we can use a vector of vectors to store sub-arrays of size K.

Below is the implementation of the above approach:

## CPP

 `// C++ implementation of the approach ` `#include ` `using` `namespace` `std; ` ` `  `// Function that returns the sub-array ` `vector<``int``> findSubarray(``int` `a[], ``int` `k, ``int` `n) ` `{ ` ` `  `    ``// Data-structure to store all ` `    ``// the sub-arrays of size K ` `    ``vector > vec; ` ` `  `    ``// Iterate to find all the sub-arrays ` `    ``for` `(``int` `i = 0; i < n - k + 1; i++) { ` `        ``vector<``int``> temp; ` ` `  `        ``// Store the sub-array elements in the array ` `        ``for` `(``int` `j = i; j < i + k; j++) { ` `            ``temp.push_back(a[j]); ` `        ``} ` ` `  `        ``// Push the vector in the container ` `        ``vec.push_back(temp); ` `    ``} ` ` `  `    ``// Sort the vector of elements ` `    ``sort(vec.begin(), vec.end()); ` ` `  `    ``// The last sub-array in the sorted order ` `    ``// will be the answer ` `    ``return` `vec[vec.size() - 1]; ` `} ` ` `  `// Driver code ` `int` `main() ` `{ ` `    ``int` `a[] = { 1, 4, 3, 2, 5 }; ` `    ``int` `k = 4; ` `    ``int` `n = ``sizeof``(a) / ``sizeof``(a); ` ` `  `    ``// Get the sub-array ` `    ``vector<``int``> ans = findSubarray(a, k, n); ` ` `  `    ``for` `(``auto` `it : ans) ` `        ``cout << it << ``" "``; ` `} `

## Python3

 `# Python3 implementation of the approach ` ` `  `# Function that returns the sub-array ` `def` `findSubarray(a, k, n): ` ` `  `    ``# Data-structure to store all ` `    ``# the sub-arrays of size K ` `    ``vec``=``[] ` ` `  `    ``# Iterate to find all the sub-arrays ` `    ``for` `i ``in` `range``(n``-``k``+``1``): ` `        ``temp``=``[] ` ` `  `        ``# Store the sub-array elements in the array ` `        ``for` `j ``in` `range``(i,i``+``k): ` `            ``temp.append(a[j]) ` ` `  `        ``# Push the vector in the container ` `        ``vec.append(temp) ` ` `  `    ``# Sort the vector of elements ` `    ``vec``=``sorted``(vec) ` ` `  `    ``# The last sub-array in the sorted order ` `    ``# will be the answer ` `    ``return` `vec[``len``(vec) ``-` `1``] ` ` `  `# Driver code ` ` `  `a ``=``[ ``1``, ``4``, ``3``, ``2``, ``5` `] ` `k ``=` `4` `n ``=` `len``(a) ` ` `  `# Get the sub-array ` `ans ``=` `findSubarray(a, k, n) ` ` `  `for` `it ``in` `ans: ` `    ``print``(it,end``=``" "``) ` `     `  `# This code is contributed by mohit kumar 29 `

Output:

```4 3 2 5
```

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Improved By : mohit kumar 29

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