#include<iostream>
#include<string>
#include<vector>
#include<queue>
#include<stack>
#include<map>
#include<set>
#include<algorithm>
#include<functional>
#include<cstdio>
#include<cstdlib>
#include<cmath>
#include<cassert>
#include<ctime>
using namespace std;

#define mind(a,b) (a>b?b:a)
#define maxd(a,b) (a>b?a:b)
#define absd(x) (x<0?-(x):x)
#define pow2(x) ((x)*(x))
#define rep(i,n) for(int i=0; i<n; ++i)
#define repr(i,n) for(int i=n-1; i>=0; --i)
#define repl(i,s,n) for(int i=s; i<=n; ++i)
#define replr(i,s,n) for(int i=n; i>=s; --i)
#define repf(i,s,n,j) for(int i=s; i<=n; i+=j)
#define repe(e,obj) for(auto e : obj)

#define SP << " " <<
#define COL << " : " <<
#define COM << ", " <<
#define ARR << " -> " <<
#define PNT(STR) cout << STR << endl
#define POS(X,Y) "(" << X << ", " << Y << ")"
#define DEB(A) " (" << #A << ") " << A
#define DEBREP(i,n,val) for(int i=0; i<n; ++i) cout << val << " "; cout << endl
#define ALL(V) (V).begin(), (V).end()
#define INF 1000000007
#define INFLL 1000000000000000007LL
#define EPS 1e-9

typedef unsigned int uint;
typedef unsigned long ulong;
typedef unsigned long long ull;
typedef long long ll;
typedef long double ld;
#define P_TYPE int
typedef pair<P_TYPE, P_TYPE> P;
typedef pair<P, P_TYPE> PI;
typedef pair<P_TYPE, P> IP;
typedef pair<P, P> PP;
typedef priority_queue<P, vector<P>, greater<P> > pvqueue;

int n, m;
priority_queue<IP, vector<IP>, greater<IP> > que;

#define N 103
int parent[N];

int root(int x) {
  if(x == parent[x]) return x;
  return parent[x] = root(parent[x]);
}

void unite(int x, int y) {
  int px = root(x), py = root(y);
  if(px < py) {
    parent[py] = px;
  } else if(px > py) {
    parent[px] = py;
  }
}

int main() {
  while(cin >> n >> m && n && m) {
    rep(i, m) {
      int a, b, cost;
      cin >> a >> b >> cost;
      que.push(IP(cost, P(a, b)));
    }
    rep(i, n) parent[i] = i;
    int ans = 0;
    while(!que.empty()) {
      IP e = que.top(); que.pop();
      int cost = e.first, a = e.second.first, b = e.second.second;
      if(root(a) != root(b)) {
        unite(a, b);
        ans += cost;
      }
    }
    cout << ans << endl;
  }
  return 0;
}