HDU 2544
#include
#include
#include
#include
#include
#include
#include
#include
#define MAXN 105
#define MAXM 305
#define MOD 10000
#define inf 100000000
#define eps 1e-9
#define pi acos(-1.0)
typedef long long LL;
using namespace std;
int n, m, c, u, v, w, mat[MAXN][MAXN], dis[MAXN];
bool vis[MAXN];
void Dijkstra() {
memset(vis, false, sizeof(vis));
memset(dis, 0x3f, sizeof(dis)); dis[1] = 0;
for (int i = 1; i < n; i++) {
int k = -1;
for (int j = 1; j <= n; j++) {
if (!vis[j] && (k == -1 || dis[j] < dis[k]))
k = j;
}
vis[k] = true;
for (int j = 1; j <= n; j++) {
if (!vis[j] && mat[k][j] && dis[k] + mat[k][j] < dis[j])
dis[j] = dis[k] + mat[k][j];
}
}
}
int main() {
//freopen("in.txt", "r", stdin);
//freopen("out.txt", "w", stdout);
while (scanf("%d %d", &n, &m) && (n || m)) {
memset(mat, 0, sizeof(mat));
for (int i = 1; i <= m; i++) {
scanf("%d %d %d", &u, &v, &w);
mat[u][v] = mat[v][u] = w;
}
Dijkstra();
printf("%d\n", dis[n]);
}
return 0;
}
