#include <stdio.h>

#include <stdlib.h>

#include <string.h>



#define MAXN 100

#define INF 4000000L



int n, m;

unsigned long int (*d)[MAXN], (*q)[MAXN];



int main(void)

{

  FILE *f, *g;

  int i, j, k;

  int x, y;

  unsigned long int z, z0;



  d = malloc(sizeof(long int) * MAXN * MAXN);

  q = malloc(sizeof(long int) * MAXN * MAXN);

  if (!d || !q) return 1;



  f = fopen("trip.in", "r");

  if (!f || fscanf(f, "%d%d", &n, &m) != 2)

    return 1;



  for(i=0; i<n; i++)

    for(j=0; j<n; j++)

      d[i][j] = q[i][j] = INF;



  for(i=0; i<m; i++)

    {

      fscanf(f, "%d%d%ld", &x, &y, &z);

      x--, y--;

      if (d[x][y] > z && x != y)

	d[x][y] = d[y][x] = z;

    }

  fclose(f);



  z = INF;

  x = y = 0;

  for(i=0; i<n; i++)

    {

      q[i][i] = 0;

      for(j=0; j<i; j++)

        for(k=0; k<i; k++) // staci od k=j+1 testovat

	  if (j != k)

	    {

	      z0 = q[j][k] + d[i][j] + d[i][k];

	      if (z0 < z)

		{

		  z = z0;

		  x = i;

		  y = j;

		}

	    }

      for(j=0; j<i; j++)

	{

          q[i][j] = INF; // Uz je nastaveno !

          for(k=0; k<i; k++)

	    if (q[i][j] > q[j][k] + d[k][i])

	      q[i][j] = q[j][k] + d[k][i];

	  q[j][i] = q[i][j];

	}

      for(j=0; j<i; j++)

	for(k=0; k<i; k++)

	  if (q[j][k] > q[j][i] + q[i][k])

	    q[j][k] = q[j][i] + q[i][k];

    }



  d[x][y] = d[y][x] = INF;



  memcpy(q, d, sizeof(long int)*MAXN*MAXN);

// memcpy(q, d, sizeof(q)); // Tohle snad ne!!

  for(i=0; i<n; i++)

    q[i][i] = 0;

  for(i=0; i<n; i++)

    for(j=0; j<n; j++)

      for(k=0; k<n; k++)

	if (q[j][k] > q[j][i] + q[i][k])

	  q[j][k] = q[j][i] + q[i][k];



  g = fopen("trip.out", "w");

  if (!g)

    return 2;

  if (z == INF)

    fprintf(g, "No solution.\n");

  else

    {

      while (x != y)

	{

	  fprintf(g, "%d ", y+1);

	  for(i=0; i<n; i++)

	    if (q[y][x] == q[i][x] + d[y][i])

	      {

		y = i;

		break;

	      }

	}

      fprintf(g, "%d\n", x+1);

    }

  fclose(g);

  return 0;

}