Count digits in given number N which divide N in C++

We are given a number let’s say, N and the task is to find the count of those digits in a number that divides the number N.

Points to be remember

• If the digit is 0 then it should be ignored which means count will not be increased for 0.

• If a digit is appearing twice and it divides the number, then the count will depend upon the digit occurrence. For example, we are given a number 2240 and in this number every digit except the 0 will divide the number and 2 is occurring twice then the count will be 2 for digit 2.

Input − number = 2240

Output − count is 3

Explanation − Break the number into digits and it will be 2, 2, 4, 0. Now check whether 2 divides 2240 if yes then increase the count else move to next digit, in this number 2, 2, 4 divides the digit 2240 so count will be 3 and ignore the digit 0 in every case.

Input − number = 755

Output − count is 2

Explanation − Break the number into digits and it will be 7, 5, 5. Now check whether 7 divides 755 if yes then increase the count else move to next digit, in this number 5, 5 divides the digit 755 so count will be 2 and ignore the digit 0 in every case

Approach used in the below program is as follows

• Input the number in a integer variable let’s say num

• Start the loop till num is greater than 0

• Inside the loop, break the number into digits and keep storing the results in a variable let’s say rem

• Check if rem divides the number if yes then increase the value of a count variable by 1 and if not then don’t increase the value of a count variable.

• And this check statement is applied when the rem is greater than 0 as we have to ignore the 0.

Example

 Live Demo

#include <bits/stdc++.h>
using namespace std;
int count(int num){
   int a=num;
   int count=0,rem;
   while(a>0){
      rem=a%10;
      if(rem > 0){
         if(num%rem==0){
            count++;
         }
      }
      a=a/10;
   }
   return count;
}
int main(){
   int num = 2240;
   cout<<"Count of digits in given number "<<num<<" which divide N are: "<<count(num);
   return 0;
}

Output

If we run the above code, we will get the following output −

Count of digits in given number 2240 which divide N are: 3