// ============================================
// Control Statements (p. 12)


double income = 0, tax = 0; 

cout << "Please enter the taxable income: ";
cin  >> income;

if(income <= 10000)
  tax = 0.02 * income;
else
  tax = 0.08 * (income - 10000) + 10000 * 0.02;

cout << "Tax amount: $" << tax << "\n";





// ============================================
// Control Statements (p. 28)


int a = 0, b = 0;

if((a > 10) && (b = 1))
  ;  
cout << b << "\n"; 

if((a > 10) || (b = 5))
  ; 
cout << b << "\n"; 





// ============================================
// Control Statements (p. 35)


int y = 0, m = 0;
cin >> y >> m;
int d = 0;

if(m == 1 || m == 3 || m == 5 || m == 7 ||
   m == 8 || m == 10 || m == 12)
  d = 31;
else if(m == 4 || m == 6 ||
        m == 9 || m == 11)
  d = 30;
else if ((y % 400 == 0) || 
         (y % 4 == 0 && (y % 100 != 0)))
  d = 29;
else
  d = 28;  
cout << d << "\n";





// ============================================
// Control Statements (p. 35)

int y = 0, m = 0;
cin >> y >> m;
int d = 0;

switch(m)
{
  case 1: case 3: case 5: case 7: 
  case 8: case 10: case 12:
    d = 31;
    break;
  case 4: case 6: case 9: case 11:
    d = 30;
    break;
  case 2:
    if((y % 400 == 0) || 
       (y % 4 == 0 && (y % 100 != 0)))
      d = 29;
    else
      d = 28; 
}
cout << d << "\n";





// ============================================
// Control Statements (p. 37)

int sum = 0;
int i = 1;

while(i <= 100)
{
  sum = sum + i;
  i = i + 1;
}

cout << sum << "\n";





// ============================================
// Control Statements (p. 37)

int exit = 0;
// do something
cout << "Press 1 to exit: ";
cin >> exit;

while(exit != 1)
{
  // do something
  cout << "Press 1 to exit: ";
  cin >> exit;
}






// ============================================
// Control Statements (p. 49)

int sum = 0;
for(int i = 1; i <= 100; i++)
  sum = sum + i;
cout << sum;




// ============================================
// Control Statements (p. 50)

for(int i = 0, j = 0; i < 10, j > -5; i++, j--)
  cout << i << " " << j << "\n";




// ============================================
// Control Statements (p. 56)

for(int x = 1; x <= 3; x++)
{
  for(int y = 1; y <= 3; y++)
    cout << "(" << x << ", " << y << ") ";
  cout << "\n";
}





// ============================================
// Control Statements (p. 58)

for(int a = 1; a <= 100; a++)
{
  if(a % 10 != 0)
    cout << a << " ";
}




// ============================================
// Control Statements (p. 58)

for(int a = 1; a <= 100; a++)
{
  if(a % 10 == 0)
    continue;
  cout << a << " ";
}




// ============================================
// Control Statements (p. 59)

int a = 0, b = 0;
while(a <= 10)
{
  while(b <= 10)
  {
    if(b == 5)
      break;
    cout << a * b << "\n";
    b++;
  }
  a++;
}
cout << a << "\n"; // ?





// ============================================
// Control Statements (p. 60)

int exit = 0;

while(true)
{
  // do something
  cout << " Press 1 to exit: ";
  cin >> exit;
  if(exit == 1)
    break;
}