#include<iostream>
using namespace std;

int gcd(int m, int n)
{
    int temp = 0;
    if (m < n)
    {
        temp = m;
        m = n;
        n = temp;
    }
    while (0 != m%n)
    {
        temp = n;
        n = m%n;
        m = n;
    }
    return n;
}

int main()
{
    int m =0, n =0;
    cin>>m>>n;
    cout<<gcd(m, n)<<endl;
    return 0;
}

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