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# Count of indices in an array that satisfy the given condition

• Difficulty Level : Easy
• Last Updated : 27 Apr, 2021

Given an array arr[] of N positive integers, the task is to find the count of indices i such that all the elements from arr to arr[i – 1] are smaller than arr[i].

Examples:

Input: arr[] = {1, 2, 3, 4}
Output:
All indices satisfy the given condition.
Input: arr[] = {4, 3, 2, 1}
Output:
Only i = 0 is the valid index.

Approach: The idea is to traverse the array from left to right and keep track of the current maximum, whenever this maximum changes then the current index is a valid index so increment the resulting counter.
Below is the implementation of the above approach:

## C++

 `// C++ implementation of the approach``#include ``using` `namespace` `std;` `// Function to return the count``// of indices that satisfy``// the given condition``int` `countIndices(``int` `arr[], ``int` `n)``{` `    ``// To store the result``    ``int` `cnt = 0;` `    ``// To store the current maximum``    ``// Initialized to 0 since there are only``    ``// positive elements in the array``    ``int` `max = 0;``    ``for` `(``int` `i = 0; i < n; i++) {` `        ``// i is a valid index``        ``if` `(max < arr[i]) {` `            ``// Update the maximum so far``            ``max = arr[i];` `            ``// Increment the counter``            ``cnt++;``        ``}``    ``}` `    ``return` `cnt;``}` `// Driver code``int` `main()``{``    ``int` `arr[] = { 1, 2, 3, 4 };``    ``int` `n = ``sizeof``(arr) / ``sizeof``(``int``);` `    ``cout << countIndices(arr, n);` `    ``return` `0;``}`

## Java

 `// Java implementation of the approach``class` `GFG``{` `// Function to return the count``// of indices that satisfy``// the given condition``static` `int` `countIndices(``int` `arr[], ``int` `n)``{` `    ``// To store the result``    ``int` `cnt = ``0``;` `    ``// To store the current maximum``    ``// Initialized to 0 since there are only``    ``// positive elements in the array``    ``int` `max = ``0``;``    ``for` `(``int` `i = ``0``; i < n; i++)``    ``{` `        ``// i is a valid index``        ``if` `(max < arr[i])``        ``{` `            ``// Update the maximum so far``            ``max = arr[i];` `            ``// Increment the counter``            ``cnt++;``        ``}``    ``}``    ``return` `cnt;``}` `// Driver code``public` `static` `void` `main(String[] args)``{``    ``int` `arr[] = { ``1``, ``2``, ``3``, ``4` `};``    ``int` `n = arr.length;` `    ``System.out.println(countIndices(arr, n));``}``}` `// This code is contributed by Rajput-Ji`

## Python3

 `# Python implementation of the approach` `# Function to return the count``# of indices that satisfy``# the given condition``def` `countIndices(arr, n):` `    ``# To store the result``    ``cnt ``=` `0``;` `    ``# To store the current maximum``    ``# Initialized to 0 since there are only``    ``# positive elements in the array``    ``max` `=` `0``;``    ``for` `i ``in` `range``(n):``        ``# i is a valid index``        ``if` `(``max` `< arr[i]):` `            ``# Update the maximum so far``            ``max` `=` `arr[i];` `            ``# Increment the counter``            ``cnt ``+``=` `1``;` `    ``return` `cnt;` `# Driver code``if` `__name__ ``=``=` `'__main__'``:``    ``arr ``=` `[ ``1``, ``2``, ``3``, ``4` `];``    ``n ``=` `len``(arr);` `    ``print``(countIndices(arr, n));` `# This code is contributed by 29AjayKumar`

## C#

 `// C# implementation of the approach``using` `System;``    ` `class` `GFG``{` `// Function to return the count``// of indices that satisfy``// the given condition``static` `int` `countIndices(``int` `[]arr, ``int` `n)``{` `    ``// To store the result``    ``int` `cnt = 0;` `    ``// To store the current maximum``    ``// Initialized to 0 since there are only``    ``// positive elements in the array``    ``int` `max = 0;``    ``for` `(``int` `i = 0; i < n; i++)``    ``{` `        ``// i is a valid index``        ``if` `(max < arr[i])``        ``{` `            ``// Update the maximum so far``            ``max = arr[i];` `            ``// Increment the counter``            ``cnt++;``        ``}``    ``}``    ``return` `cnt;``}` `// Driver code``public` `static` `void` `Main(String[] args)``{``    ``int` `[]arr = { 1, 2, 3, 4 };``    ``int` `n = arr.Length;` `    ``Console.WriteLine(countIndices(arr, n));``}``}` `// This code is contributed by PrinciRaj1992`

## Javascript

 ``
Output:
`4`

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