# C/C++ Program to check whether it is possible to make a divisible by 3 number using all digits in an array?

CC++Server Side ProgrammingProgramming

In this section we will see if one array is given with n numbers, we have to check if we make a number using all of the elements of these numbers, that number will be divisible by 3 or not. If the array elements are {15, 24, 23, 13}, then the we can make integer like 15242313. It will be divisible by 3.

## Algorithm

#### checkDivThree(arr)

Begin
rem := 0
for each element e in arr, do
rem := (rem + e) mod 3
done
if rem is 0, then
return true
end if
return false
End

## Example

#include<iostream>
#define MAX 4
using namespace std;
bool checkDivThree(int arr[], int n){
int rem = 0;
for(int i = 0; i<n; i++){
rem = (rem + arr[i]) % 3;
}
if(rem == 0){
return true;
}
return false;
}
main() {
int arr[] = {15, 24, 23, 13};
int n = sizeof(arr)/sizeof(arr);
if(checkDivThree(arr, n)){
cout << "Divisible";
}else{
cout << "Not Divisible";
}
}

## Output

Divisible