#include <iostream>
using namespace std;
int nwd(int a, int b)
{
if (a%b)
return nwd(b, a%b);
return b;
}
int x;
int main()
{
cin >> x;
for (int i = 1; i <= x; i++)
{
int a, b;
cin >> a >> b;
cout << nwd(a, b) << endl;
break;
}
return 0;
}
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