First test, Computer Sciences, Universidad de Valladolid, January 2013.

gistfile1.java

// PART 3
static void metodo3(NotaAlumnoAsignatura [] a)
{  
  int current = a[0].numAlumno;
  double total = 0;
  int nuNotas = 0;
  try {
    PrintWriter salida = new PrintWriter(new FileWriter("Notas.txt"));
    
    for(int i = 0; i < a.lenght; ++i) {
      if(current != a[i].numAlumno) {
        salida.println(a[i-1].nombre+" "+(total/nuNotas));
        total = 0;
        nuNotas = 0;
      }
      total += a[i].nota;
      ++nuNotas;
    }
    salida.println(a[a.length-1].nombre+" "+(total/nuNotas));
    salida.close();

  } catch(IOException e) {
    System.out.println("Error abriendo Notas.txt");
  }
}

gistfile2.java

// PART 1

static void binary(int nu) {
  if(nu != 0) {
    binary(nu/2);
    System.out.println((nu%2)+"");
  }
}

gistfile3.java

// PART 2
static int[] metodo1(String str) {
  int [] a = new int[10];
  for(int i = 0; i < 10; ++i)
    a[i] = -1;

  for(int i = 0; i < str.length(); ++i)
    a[(int)(str.charAt(i)-'0')] = i;

  return a;
}

static String metodo2(int [] a) {
  String str = "";
  int current = 0;
  int i = 0;
  boolean found = true;
  while(current < 10 && found == true) {
    found = false;
    while(i < a.lenght && found == false) {
      if(a[i] == current) {
        str.concat(i+"");
        found = true;
      }
      ++i;
    }
  ++current;
}

gistfile4.java

// PART 4

class NotasCurso {
  public char grupo;
  public int curso;
  public double [][] notas;

  NotasCurso() {
    this.grupo = '0';
    this.curso = 0;
    this.notas = new double[NAL][NASIGN];
    for(int x = 0; x < NAL; ++x)
      for(int y = 0; y < NASIGN; ++y)
        this.notas[x][y] = 0;
  }

  NotasCurso(char grupo, int curso, NotasAlumnoAsignatura [] a) {
    this();
    this.grupo = grupo;
    this.curso = curso;

    for(int i = 0; i < a.length; ++i)
      this.notas[a[i].numAlumno][a[i].numAsignatura] = a[i].nota;
  }

  static double mediaAlumno(NotasCurso c, int alumno) {
    double total = 0; 
    for(int i = 0; i < NASIGN; ++i)
      total += c.notas[alumno][i];

    return (total / NASIGN);
  }

  double mediaAsignatura(int asignatura) {
    double total = 0;
    for(int i = 0; i < NAL; ++i)
      total += this.notas[i][asignatura];

    return (total / NAL);
  }
}