---------------------------------------

<Selezione> ::=
     if (<EsprLogica>) <Istruzione> [else <Istruzione>]

---------------------------------------

if (x >= 0)
  System.out.println("x e' positivo");

---------------------------------------

if (x >= 0)
  System.out.println("x e' positivo");
else
  System.out.println("x e' negativo");

---------------------------------------

if (x >= 0)
  System.out.println("x e' positivo");
else
  System.out.println("x e' negativo");
  System.out.println("NON puoi calcolare la radice quadrata!!");

---------------------------------------

if (x >= 0)
  System.out.println("x e' positivo");
else {
  System.out.println("x e' negativo");
  System.out.println("NON puoi calcolare la radice quadrata!!");
}

---------------------------------------

if (x >= 0)
  if (x < 10)
    System.out.println("positivo e minore di 10");

---------------------------------------

if (x >= 0)
  if (x < 10)
    System.out.println("positivo e minore di 10");
  else
    System.out.println("positivo e maggiore o uguale a 10");

---------------------------------------

if (x >= 0)
  if (x < 10)
    System.out.println("positivo e minore di 10");
else
  System.out.println("negativo");

---------------------------------------

if (x >= 0) {
  if (x < 10)
    System.out.println("positivo e minore di 10");
} else
  System.out.println("negativo");

---------------------------------------

if (x == y)
  System.out.println("Uguali");
else if (x > y)
  System.out.println("x e' il piu' grande");
else
  System.out.println("y e' il piu' grande");

---------------------------------------

if (C1)
  if (C2) {
    if (C3)
      I1;
  } else
    I2;
else
  I3;

---------------------------------------

if (!C1)
  I3;
else if (!C2)
  I2;
else if (C3)
  I1;

---------------------------------------

if (x == y)
  System.out.println("Uguali");
else if (x > y) {
  System.out.println("x e' il piu' grande");
  z = x;
} else {
  System.out.println("y e' il piu' grande");
  z = y;
}

---------------------------------------

import java.io.*;
class Max4 {
  public static void main (String[] args) throws IOException {
    char a, b, c, d, max;

    a = (char) System.in.read();
    b = (char) System.in.read();
    c = (char) System.in.read();
    d = (char) System.in.read();
    if (a > b && a > c && a > d)
      max = a;
    else if (b > a && b > c && b > d)
      max = b;
    else if (c > a && c > b && c > d)
      max = c;
    else
      max = d;
    System.out.println(max);
  }
}

---------------------------------------

    if (a > b && a > c && a > d) {
      max = a;
      System.out.print("Il maggiore e' il primo: ");
    } else if (b > a && b > c && b > d) {
      max = b;
      System.out.print("Il maggiore e' il secondo: ");
    } else if (c > a && c > b && c > d) {
      max = c;
      System.out.print("Il maggiore e' il terzo: ");
    } else {
      max = d;
      System.out.print("Il maggiore e' il quarto: ");
    }

---------------------------------------

<IstruzioneSwitch> ::=
     switch ( <Espr> ) {
     case <Val1> : [ <Sequenza1> ] [break;]
     case <Val2> : [ <Sequenza2> ] [break;] 
     ...
     case <ValN> : [ <SequenzaN> ] [break;] 
     [ default : [ <Sequenza> ] [break;] ]
     }

---------------------------------------

switch ( C ) {
  case V1: I1; break;
  case V2: I2; break;
  ...
  case Vn: In; break;
  default : I; break;
}

---------------------------------------

    switch (c) {
    case 'a':
      System.out.println("Vocale");
      break;
    case 'e':
      System.out.println("Vocale");
      break;
    case 'i':
      System.out.println("Vocale");
      break;
    case 'o':
      System.out.println("Vocale");
      break;
    case 'u':
      System.out.println("Vocale");
      break;
    default: System.out.println("Consonante");
      break;
    }

---------------------------------------

    switch (c) {
    case 'a': // Vai al prox.
    case 'e': // Vai al prox.
    case 'i': // Vai al prox.
    case 'o': // Vai al prox.
    case 'u':
      System.out.println("Vocale");
      break;
    default: System.out.println("Consonante");
      break;
    }

---------------------------------------

    switch (giorno) {
    case 1:
      System.out.println("Lunedi'");
      break;
    case 2:
      System.out.println("Martedi'");
      break;
    case 3:
      System.out.println("Mercoledi'");
      break;
    case 4:
      System.out.println("Giovedi'");
      break;
    case 5:
      System.out.println("Venerdi'");
      break;
    case 6:
      System.out.println("Sabato");
      break;
    case 7:
      System.out.println("Domenica");
      break;
    default:
      System.out.println("Valore non lecito");
      break;
    }

---------------------------------------

IstruzioneWhile ::= while ( <EsprLogica> ) <Istruzione>

---------------------------------------

class CicloWhile {
  public static void main (String[] args)  {
    int i;

    i = 1;
    while (i <= 10) {
      System.out.println(i);
      i = i + 1;
    }
    System.out.println("Fine stampa");
  }
}

---------------------------------------

    i = 1;
    while (i <= 10) {
      if (i % 2 == 0)
        System.out.println(i);
      i = i + 1;
    }

---------------------------------------

    i = 2;
    while (i <= 10) {
      System.out.println(i);
      i = i + 2;
    }

---------------------------------------

while ("ci sono ancora voti") {
  "Leggi il prossimo voto";
  "Aggiungi a media";
}
"Stampa media / 10";

---------------------------------------

class Voti {
  public static void main (String[] args) throws IOException {
    "azzera media";
    "inizializza i";
    while (i <= 10) {
      "Leggi voto";
      if (voto == 'O')
        "Aggiungi 10 a media";
      else if (voto == 'B')
        "Aggiungi 8 a media";
      else if (voto == 'S')
        "Aggiungi 6 a media";
      else if (voto == 'I')
        "Aggiungi 4 a media";
      "incrementa i";
     }
     "Stampa media / 10";
  }
}

---------------------------------------

/* Programma per calcolare la media dei voti*/
import java.io.*;
class Voti {
  public static void main (String[] args) throws IOException {
    int voto, media, i;
    media = 0;
    i = 1;
    while (i <= 10) {
      voto = System.in.read();
      if (voto == 'O')
        media = media + 10;
      else if (voto == 'B')
        media = media + 8;
      else if (voto == 'S')
        media = media + 6;
      else if (voto == 'I')
        media = media + 4;
      i = i + 1;
    }
    media = media / 10;
    System.out.print("Media = ");
    System.out.println(media);
  }
}

---------------------------------------

      if (voto == 'O')
        media = media + 10;
      else
        if (voto == 'B')
          media = media + 8;
        else
          if (voto == 'S')
            media = media + 6;
          else
            if (voto == 'I')
              media = media + 4;

---------------------------------------

switch (voto) {
case 'O':
    media = media + 10;
    break;
case 'B':
    media = media + 8;
    break;
case 'S':
    media = media + 6;
    break;
case 'I':
    media = media + 4;
    break;
}

---------------------------------------

<IstruzioneDoWhile> ::= do <Istruzione> while (<EsprLogica>)

---------------------------------------

do {
  I
} while (C);

---------------------------------------

{
  I;
  while (C)
    I;
}

---------------------------------------

    do {
      c = System.in.read();
    } while ((c != 'n') && (c != 's'));

---------------------------------------

  } while ...

---------------------------------------

<IstruzioneFor> ::=
  for (<Istruzione>; <EsprLogica>; <Istruzione>) <Istruzione>

---------------------------------------

for (i = 1; i <= 10; i = i + 1)
  System.out.println(i);

---------------------------------------

for (I1; C; I2)
  I3;

---------------------------------------

I1;
while (C) {
  I3;
  I2;
}

---------------------------------------

for (i = 10; i >= 1; i = i - 1)
  System.out.println(i);

---------------------------------------

for (i = 2; i <= 10; i = i + 2)
  System.out.println(i);

---------------------------------------

for (int i = 1; i <= 10; i = i + 1)
  System.out.println(i);

---------------------------------------

for (i = 1; i <= 10; i = i + 1);
System.out.println(i);

---------------------------------------

for (; ; ;)
  I

---------------------------------------

while (true)
  I

---------------------------------------

for (i = 1; i <= 10; i++)
  System.out.println(i);

---------------------------------------

for (i = 10; i >=1; i--)
  System.out.println(i);

---------------------------------------

i = 1;
a = ++i;

---------------------------------------

i = 1;
a = i++;

---------------------------------------

for (i = 1; i <= 5; i++) {
  for (j = 1; j <= 10; j++)
    System.out.print('*');
  System.out.println();
}

---------------------------------------

**********
**********
**********
**********
**********

---------------------------------------

for (i = 1; i <= 5; i++) {
  for (j = 1; j <= i; j++)
    System.out.print('*');
  System.out.println();
}

---------------------------------------

*
**
***
****
*****

---------------------------------------

i = 0;
while (i <= 10) {
  System.out.println(i);
}

---------------------------------------

i = 1;
while (i != 10) {
  System.out.println(i);
  i = i + 2;
}

---------------------------------------

i = 1;
do {
  System.out.println(i);
  i++;
} while (i < 10);

---------------------------------------

i = 1;
do {
  i++;
  System.out.println(i);
} while (i < 10);

---------------------------------------

i = 0;
do {
  i++;
  System.out.println(i);
} while (i < 10);

---------------------------------------

i = 1;
while (i <= 10) {
  System.out.println(i);
  i++;
}

---------------------------------------

for (i = 1; i <= 10; i++)
    System.out.println(i);

---------------------------------------

i = 0;
while (i <= 9) {
  i++;
  System.out.println(i);
}

---------------------------------------

for (i = 1; i <= 10; i++) {
  if (i == 5)
    break;
  System.out.println(i);
}
System.out.println("Fuori dal ciclo");

---------------------------------------

for (i = 1; i <= 10; i++) {
  if (i == 5)
    continue;
  System.out.println(i);
}
System.out.println("Fuori dal ciclo");

---------------------------------------

pippo: {
  for (int i = 1; i <= 10; i++) {
    for (int j = 1; j <= 10; j++) {
      System.out.print('*');
      if ((i == 7) && (j == 9)) break pippo;
    }
    System.out.println();
  }
}

---------------------------------------

i = 1;
while (i <= 10) {
  if (i == 5)
    break;
  System.out.println(i);
  i++;
}

---------------------------------------

i = 1;
while (i <= 10 && !(i == 5)) {
  System.out.println(i);
  i++;
}

---------------------------------------

for (i = 1; i <= 10; i++) {
  if (i == 5)
    break;
  System.out.println(i);
}

---------------------------------------

for (i = 1; i <= 10; i++) {
  if (i == 5)
    continue;
  System.out.println(i);
}

---------------------------------------

for (i = 1; i <= 10; i++) {
  if (!(i == 5))
    System.out.println(i);
}

---------------------------------------

"Per i che va da 1 al minimo fra x e y"
  "se i divide x e y allora metto i in mcd"
"Stampo mcd"

---------------------------------------

for (i = 1; i <= "minimo fra x e y"; i++) {
  if ("i e' un divisore di x e y")
    mcd = i;
}
"Stampo mcd"

---------------------------------------

for (i = 1; i <= ((x < y)? x : y); i++) {
  if ((x % i == 0) && (y % i == 0))
    mcd = i;
}
System.out.println(mcd);

---------------------------------------

for (i = ((x < y)? x : y); i >= 1; i--)
  if ((x % i == 0) && (y % i == 0)) {
    mcd = i;
    break;
}
System.out.println(mcd);

---------------------------------------

mcd = 1;
i = ((x < y)? x : y);
while (i >= 1 && mcd == 1) {
  if ((x % i == 0) && (y % i == 0))
    mcd = i;
  i--;
}
System.out.println(mcd);

---------------------------------------

min = ((x < y)? x : y);
if ((x % min == 0) && (y % min == 0))
  mcd = min;
else
  for (i = min/2; i >= 1; i--)
    if ((x % i == 0) && (y % i == 0)) {
      mcd = i;
      break;
    }
System.out.println(mcd);

---------------------------------------

while (x!=y)
  if (x>y)
    x = x - y;
  else
    y = y - x;
System.out.println(x);

---------------------------------------

*         *****     *****         *     **             *
**        ****       ****        **     ****           ***
***       ***         ***       ***     ******         *****
****      **           **      ****     ********       *******
*****     *             *     *****     **********     *********

---------------------------------------

for (i = 1; i <= 5; i++) {
  for (j = 1; j <= i; j++)
    System.out.print('*');
  System.out.println();
}

for (i = 1; i <= 5; i++) {
  for (j = i; j <= 5; j++)
    System.out.print('*');
  System.out.println();
}

for (i = 1; i <= 5; i++) {
  for (j = 1; j <= 5; j++)
    if (i > j)
      System.out.print(' ');
    else
      System.out.print('*');
  System.out.println();
}

for (i = 1; i <= 5; i++) {
  for (j = 5; j >=1; j--)
    if (i < j)
      System.out.print(' ');
    else
      System.out.print('*');
  System.out.println();
}

for (i = 1; i <= 5; i++) {
  for (j = 1; j <= 2*i; j++)
    System.out.print('*');
  System.out.println();
}

for (i = 1; i <= 5; i++) {
  for (j = 1; j <= 2*i-1; j++)
    System.out.print('*');
  System.out.println();
}

---------------------------------------

/* Programma per stampare 44 caratteri in fila per 6 con 
 * resto di 2 */
import java.io.*;
class Gatti {
  public static void main (String[] args) throws IOException {
    char c;
    for (int i = 1; i <= 44; i++) {
      c = (char) System.in.read();
      System.out.print(c);
      if (i % (44 / 6) == 0)
        System.out.println();
    }
    System.out.println();
  }
}

---------------------------------------

>java Gatti
quarantaquattrogattiinfilaperseiconrestodidu
quarant
aquattr
ogattii
nfilape
rseicon
restodi
du

---------------------------------------

class Prova {
  public static void main (String[] args) {
    for (double x = 0.1; x != 1.0; x = x + 0.1)
      System.out.println(x);
  }
}

---------------------------------------

>java Prova
0.1
0.2
0.30000000000000004
0.4
0.5
0.6
0.7
0.7999999999999999
0.8999999999999999
0.9999999999999999
1.0999999999999999
1.2
1.3
1.4000000000000001

---------------------------------------

class Prova {
  public static void main (String[] args) {
    for (int x = 1; x <= 10; x++)
      System.out.println((double) x/10);
  }
}

---------------------------------------

0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0

---------------------------------------

for (int i = 3; i <= 100; i++)
  for (int j = 3; j <= 100; j++) 
    if (i * j <= 100)
      System.out.println(i + " " + j + " " + i * j);

---------------------------------------

for (int i = 3; i <= 100; i++)
  for (int j = 3; j <= 100; j++)
    for (int k = 3; k <= 100; k++)
      if (i * j != k)
        System.out.println(i + " " + j + " " + k);