/* ------------------------------------ */
/*exo1.c*/
/* ------------------------------------ */

#include<stdio.h>

int main (void)
{
  int i;
  i = 1;

  while (i<=50)
    {
      printf("%d ",i);
      i=i+1;
    }
  ;

  printf("\n");
  return 0;
}
/* ------------------------------------ */
/*exo2.c*/
/* ------------------------------------ */

#include<stdio.h>

int main (void)
{
  int i;
  i = 50;

  while (i>=1)
    {
      printf("%d ",i);
      i=i-1;
    }
  ;

  printf("\n");
  return 0;
}
/* ------------------------------------ */
/*exo3.c*/
/* ------------------------------------ */

#include<stdio.h>
#include<fonctions.c>

int main (void)
{
  int ent1,ent2;
  int imin,imax,i;

  scanf("%d %d",&ent1,&ent2);
  imin = min(ent1,ent2);
  imax = max(ent1,ent2);

  i = imin;

  while (i<=imax)
    {
      if (i%2 == 0) {printf("%d ",i);};
      i=i+1;
    }
  ;

  printf("\n");
  return 0;
}
/* ------------------------------------ */
/*exo4.c*/
/* ------------------------------------ */

#include<stdio.h>
#include<stdlib.h>

int calcule_suivant(int u)
{
  if (u%2 == 0)
    {return (u/2);}
  else
    {return (3*u+1);}
  ;
}

int main (void)
{
  int A;
  int res,compteur;

  scanf("%d",&A);
  res = A;
  compteur = 0;
  
  while (res!=1)
    {
      res = calcule_suivant(res);
      printf(" %d\n",res);
      compteur = compteur + 1;
    }
  ;

  printf("resultat : U_%d=1 \n",compteur);
  return 0;
}
/* ------------------------------------ */
/*exo5.c*/
/* ------------------------------------ */

#include<stdio.h>
#include<fonctions.c>



int main (void)
{
  int note_courante;
  int min_tmp;
  int max_tmp;
  int nb_notes;
  int somme_tmp;
  double moyenne;

  /*initialisation obligatoire*/
  scanf("%d",&note_courante);
  nb_notes = 0;
  somme_tmp = 0;

  while (note_courante != -1)
    {
      nb_notes = nb_notes+1;
      
      /*le premier tour*/
      if (nb_notes == 1)
	{
	  min_tmp = note_courante;
	  max_tmp = note_courante;
	  somme_tmp = note_courante;
	}
      else
	{
	  somme_tmp = somme_tmp + note_courante;
	  min_tmp = min(min_tmp,note_courante);
	  max_tmp = max(max_tmp,note_courante);
	};

      scanf("%d",&note_courante);
    };
  
  if (nb_notes != 0)
    {
      moyenne = ((double) somme_tmp) / ((double) nb_notes);
      printf("%d notes de %d/20 a %d/20, moyenne %f/20\n",nb_notes,min_tmp,max_tmp,moyenne);
    };
  return 0;
}