# Thread: c++ program-the number of common digits of 2 numbers a & b

1. ## c++ program-the number of common digits of 2 numbers a & b

Hello guys!
I have to make a program that displays the k number of common digits of 2 numbers a and b.
For example if a is 23456 and b is 456900 then the number of common digits is 3(4,5 and 6).
Do I need an array that can hold the values of the digits?
I can remove the digits from the numbers and then put them in two arrays but I need help.
Is this the good way for my program or should I try something else? 2. Define a 10 element int array, initialized to zero. Loop through digits of first number, incrementing corresponding element. Loop through digits of second number, reading corresponding element. If > zero, you have a match; decrement the element. 3. I've tried to solve it but I couldn't. Please take a look at my code :
Code:
```#include<iostream>
using namespace std;

int main()
{
int dg1,dg2,a,b,i = 0,j = 0,k = 0;

cout  << "a = ";
cin >> a;

cout << "b = ";
cin >> b;

while (a) {

dg1[i] = a % 10; a/= 10;i++;

}

while (b) {

dg2[j] = b % 10; b/= 10; j++;

}

if (dg1[i] == dg2[j]) {

k++;
cout << k << "\n";

}

return 0;
}```
It's not working. What's the problem and how should I fix it? 4. You fail completely to understand the logic of a program. Furthermore, you add useless variables that do nothing.
Go write a proper flowchart to illustrate the logic of how such a program would work, then come back if you have any trouble. Popular pages Recent additions 