[백준 9613] GCD합<Java>

package d0222;

import java.util.Scanner;

public class GCD합 {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int t = sc.nextInt();
		for (int tc = 0; tc < t; tc++) {
			int n = sc.nextInt();
			int []arr = new int[n];
			for(int i=0;i<n;i++) {
				arr[i] = sc.nextInt();
			}
			long sum=0;//처음에 int여서 틀림..
			for(int i=0;i<n;i++) {
				for(int j=i;j<n;j++) {
					if(i!=j) {
						sum+=gcd(arr[i],arr[j]);
					}
				}
			}
			System.out.println(sum);
		}
	}
	
	
	public static int gcd(int a, int b) {
		if(b==0) return a;
		return gcd(b,a%b);
	}
}