CF 389A：Fox and Number Game

#include <cstdio>
#include <iostream>
using namespace std;

int num[105] = {0} ;

int gcd(int x , int y) {
return (x % y == 0)? y : gcd(y , x % y) ;
}

int main() {
int n ;
cin >> n ;
for (int i = 0 ; i < n ; i ++) {
cin >> num[i] ;
}

for (int i = 1 ; i < n ; i ++) {
if (num[0] > num[i]) num[0] = gcd(num[0] , num[i]) ;
else if (num[0] < num[i]) num[0] = gcd(num[i] , num[0]) ;
}

cout << num[0] * n << endl ;
return 0 ;
}