#include<bits/stdc++.h>
using namespace std;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
#pragma GCC optimize("Ofast,no-stack-protector,unroll-loops,fast-math,O3")
long long gcd(long long a, long long b){
if(b == 0)
return a;
return gcd(b, a % b);
}
int main(){
cin.tie(0);
cin.sync_with_stdio(0);
long long n, m;
cin>>n>>m;
long long sum = 0;
long long a[n];
long long g = __gcd(n, m);
for(int i = 0; i < n; i++){
cin>>a[i];
sum += a[i] % g;
sum %= g;
}
if(sum == 0){
cout<<gcd(m, n)<<"\n";
}else{
cout<<"0\n";
}
}
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