Check all the elements in an array are even using library in C++

We are given an array of elements and we have to check the whether each element is even or not.


Input : [2, 4, 6, 8, 9]
Output : All the elements are not even

Input : [4, 6, 8, 12, 14]
Output : Alla the elements are even

Approach: The above problem can be solved using for loop but in C++ we have all_of() algorithm which operates on whole array and save time to write code for loop and checks each element for the specified property.

Note that all_of() also uses loop internally, it just saves our time of writing a loop code.





// CPP program to check if all elements
// of an array are even or odd.
#include <algorithm>
#include <iostream>
using namespace std;
void even_or_not(int arr[], int len)
    // all_of() returns true if given operation is true
    // for all elements, otherwise returns false.
    all_of(arr, arr + len, [](int i) { return i % 2; }) ? 
                        cout << "All are even elements"
                        cout << "All are not even elements";
int main()
    int arr[] = { 2, 4, 6, 12, 14, 17 };
    int len = sizeof(arr) / sizeof(arr[0]);
    even_or_not(arr, len);
    return 0;



All are not even elements

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