#include<stdio.h>#include<string.h>#include<stdlib.h>#include<iostream>using namespace std;int n,m;struct A{int a,b;int len;}E[10101];int set[111];int cmp(const void *a,const void *b){struct A *c,*d;c=(struct A *)a;d=(struct A *)b;return c->len-d->len;}void build(int num){int i;for(i=1;i<=num;i++)set[i]=i;}int find(int k){if(set[k]==k)return k;set[k]=find(set[k]);return set[k];}void Union(int f1,int f2){set[f1]=f2;}int Kruskal(){int ans;int i;int f1,f2;ans=0;for(i=0;i<m;i++){f1=find(E[i].a);f2=find(E[i].b);if(f1==f2)continue;Union(f1,f2);ans+=E[i].len;}return ans;}int main(){int i;while(scanf("%d",&n),n){build(n);scanf("%d",&m);for(i=0;i<m;i++)scanf("%d%d%d",&E[i].a,&E[i].b,&E[i].len);qsort(E,m,sizeof(E[0]),cmp);printf("%dn",Kruskal());}return 0;}
