import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner scanner=new Scanner(System.in);
		int total=0;
		while(scanner.hasNext())
		{
			String temp=scanner.nextLine();
			total=Integer.parseInt(temp);
			if(total!=0)
			readData(total,scanner);
		}

	}

	private static void readData(int total, Scanner scanner) {
		int g[][]=new int[total][total];
		for(int i=0;i<total;i++)
			for(int j=0;j<total;j++)
		   {
			g[i][j]=1000000;
		   }
		for(int i=0;i<total*(total-1)/2;i++)
		{
			String s=scanner.nextLine();
			String buffer[]=s.split(" ");
			g[Integer.parseInt(buffer[0])-1][Integer.parseInt(buffer[1])-1]=Integer.parseInt(buffer[2]);
			g[Integer.parseInt(buffer[1])-1][Integer.parseInt(buffer[0])-1]=Integer.parseInt(buffer[2]);
		}
		calculateMinRoad(total,g);
		
	}

	private static void calculateMinRoad(int total, int[][] g) {
		int set[]=new int[total];
		int minRoad=0;
		for(int i=0;i<total;i++)
		{
			set[i]=0;
		}
		set[0]=1;
		for(int k=1;k<=total-1;k++)
		{
			int min=1000000;
			int q=0;
			for(int i=0;i<total;i++)
			{  
				if(set[i]==1)
				 for(int j=0;j<total;j++)	
					 if(set[j]==0)
						 if(g[i][j]<min)
						 {
							 min=g[i][j];
							 q=j;
						 }
				
			}
			set[q]=1;
			minRoad+=min;
		}
		System.out.println(minRoad);
	}

}

/**************************************************************
	Problem: 2188
	User: admin
	Language: Java
	Result: Accepted
	Time:962 ms
	Memory:60740 kb
****************************************************************/