Нужно разобраться с кодами - C#

// Проанализируйте код и исправьте ошибки 
 
using System; 
 
class MyClass {  
  private int alpha; // private access explicitly specified 
  int beta;          // private access by default 
  public int gamma;  // public access 
 
  /* Methods to access alpha and beta.  It is OK for a 
     member of a class to access a private member 
     of the same class. 
  */ 
  public void setAlpha(int a) { 
    alpha = a;  
  } 
 
  public int getAlpha() { 
    return alpha; 
  } 
 
  public void setBeta(int a) { 
    beta = a;  
  } 
 
  public int getBeta() { 
    return beta; 
  } 
}  
  
class AccessDemo {  
  public static void Main() {  
    MyClass ob = new MyClass();  
  
    ob.setAlpha(-99); 
    ob.setBeta(19); 
    Console.WriteLine("ob.alpha is " + ob.getAlpha()); 
    Console.WriteLine("ob.beta is " + ob.getBeta()); 
 
    ob.alpha = 10; 
    ob.beta = 9;
    Console.WriteLine("ob.alpha is " + ob.alpha());
    Console.WriteLine("ob.beta is " + ob.beta()); 
 
    ob.gamma = 99;
    Console.WriteLine("ob.gamma is " + ob.gamma());
  }  
}// Проанализируйте код и объясните результаты  
using System;  
class MyClass {  
  int alpha, beta; 
  
  public MyClass(int i, int j) {  
    alpha = i;  
    beta = j;  
  }    
  
  public bool sameAs(MyClass ob) {  
    if((ob.alpha == alpha) & (ob.beta == beta)) 
       return true;  
    else return false;  
  }  
 
  public void copy(MyClass ob) { 
    alpha = ob.alpha; 
    beta  = ob.beta; 
  } 
 
  public void show() { 
    Console.WriteLine("alpha: {0}, beta: {1}", 
                      alpha, beta); 
  } 
}    
class PassOb {  
  public static void Main() { 
    MyClass ob1 = new MyClass(4, 5);  
    MyClass ob2 = new MyClass(6, 7);  
    Console.Write("ob1: "); 
    ob1.show();  
    Console.Write("ob2: "); 
    ob2.show(); 
    if(ob1.sameAs(ob2))  
      Console.WriteLine("ob1 and ob2 have the same values."); 
    else 
      Console.WriteLine("ob1 and ob2 have different values.");  
    Console.WriteLine();  
    ob1.copy(ob2);  
    Console.Write("ob1 after copy: "); 
    ob1.show(); 
 
    if(ob1.sameAs(ob2))  
      Console.WriteLine("ob1 and ob2 have the same values."); 
    else 
      Console.WriteLine("ob1 and ob2 have different values.");  
  }  
}  // Проанализируйте код и объясните результаты 

using System; 
 
class Test { 
  /* This method causes no change to the arguments 
     used in the call. */ 
  public void noChange(int i, int j) { 
    i = i + j; 
    j = -j;
    Console.WriteLine("i and j: " +
                       i + " " + j);
} 
} 
 
class CallByValue { 
  public static void Main() { 
    Test ob = new Test(); 
 
    int a = 15, b = 20; 
 
    Console.WriteLine("a and b before call: " + 
                       a + " " + b); 
 
    ob.noChange(a, b);  
 
    Console.WriteLine("a and b after call: " + 
                       a + " " + b); 
  } 
}// Проанализируйте код и объясните результаты 
 
using System; 
 
class Test { 
  public int a, b; 
 
  public Test(int i, int j) { 
    a = i; 
    b = j; 
  }
  /* Pass an object. Now, ob.a and ob.b in object 
     used in the call will be changed. */ 
  public void change(Test ob) { 
    ob.a = ob.a + ob.b; 
    ob.b = -ob.b; 
  } 
} 
 
class CallByRef { 
  public static void Main() { 
    Test ob = new Test(15, 20); 
 
    Console.WriteLine("ob.a and ob.b before call: " + 
                       ob.a + " " + ob.b); 
 
    ob.change(ob); 
 
    Console.WriteLine("ob.a and ob.b after call: " + 
                       ob.a + " " + ob.b); 
  } 
}// Проанализируйте код и объясните результаты 
 
using System; 
 
class RefTest { 
  public void sqr(ref int i) { 
    i = i * i; 
  } 
} 
 
class RefDemo { 
  public static void Main() { 
    RefTest ob = new RefTest(); 
 
    int a = 10; 
 
    Console.WriteLine("a before call: " + a); 
 
    ob.sqr(ref a); // notice the use of ref 
 
    Console.WriteLine("a after call: " + a); 
  } 
}// Проанализируйте код и объясните результаты 
 
using System; 
 
class Swap { 
  public void swap(ref int a, ref int b) { 
    int t; 
  
    t = a; 
    a = b; 
    b = t; 
  } 
} 
 
class SwapDemo { 
  public static void Main() { 
    Swap ob = new Swap(); 
 
    int x = 10, y = 20; 
 
    Console.WriteLine("x and y before call: " + x + " " + y); 
 
    ob.swap(ref x, ref y);  
 
    Console.WriteLine("x and y after call: " + x + " " + y); 
  } 
}// Проанализируйте код и объясните результаты 
 
using System; 
 
class Decompose { 
 
  public int parts(double n, out double frac) { 
    int whole; 
 
    whole = (int) n; 
    frac = n - whole; // pass fractional part back through frac 
    return whole; // return integer portion 
  } 
} 
  
class UseOut { 
  public static void Main() {   
   Decompose ob = new Decompose(); 
    int i; 
    double f; 
 
    i = ob.parts(10.125, out f); 
 
    Console.WriteLine("Integer portion is " + i); 
    Console.WriteLine("Fractional part is " + f); 
  } 
}// Проанализируйте код и объясните результаты 
 
using System; 
 
class RefSwap { 
  int a, b; 
   
  public RefSwap(int i, int j) { 
    a = i; 
    b = j; 
  } 
 
  public void show() { 
    Console.WriteLine("a: {0}, b: {1}", a, b); 
  } 
 
  public void swap(ref RefSwap ob1, ref RefSwap ob2) { 
    RefSwap t; 
  
    t = ob1; 
    ob1 = ob2; 
    ob2 = t; 
  } 
} 
 
class RefSwapDemo { 
  public static void Main() { 
    RefSwap x = new RefSwap(1, 2); 
    RefSwap y = new RefSwap(3, 4); 
 
    Console.Write("x before call: "); 
    x.show(); 
 
    Console.Write("y before call: "); 
    y.show(); 
 
    Console.WriteLine(); 
 
    // exchange the objects to which x and y refer 
    x.swap(ref x, ref y);  
 
    Console.Write("x after call: "); 
    x.show(); 
 
    Console.Write("y after call: "); 
    y.show(); 
 
  } 
}  // Проанализируйте код и объясните результаты 
 
using System; 
 
class MyClass { 
  public int Val(params int[] nums) { 
    int m; 
 
    if(nums.Length == 0) { 
      Console.WriteLine("Error: no arguments."); 
      return 0; 
    } 
 
    m = nums[0]; 
    for(int i=1; i < nums.Length; i++)  
      if(nums[i] < m) m = nums[i]; 
 
    return m; 
  } 
} 
 
class ParamsDemo { 
  public static void Main() { 
    MyClass ob = new MyClass(); 
    int result; 
 
    int[] args = { 45, 67, 34, 9, 112, 8 }; 
    result = ob.Val(args); 
    Console.WriteLine("Result is " + result); 
  } 
}// Проанализируйте код и объясните результаты 
 
using System; 
 
class Rect { 
  int width; 
  int height; 
 
  public Rect(int w, int h) { 
    width = w; 
    height = h; 
  } 
 
  public int area() { 
    return width * height; 
  } 
 
  public void show() { 
    Console.WriteLine(width + " " + height); 
  } 
 
  /* Return a rectangle that is a specified 
     factor larger than the invoking rectangle. */ 
  public Rect enlarge(int factor) { 
    return new Rect(width * factor, height * factor); 
  } 
} 
  
class RetObj { 
  public static void Main() {   
    Rect r1 = new Rect(4, 5); 
 
    Console.Write("Dimensions of r1: "); 
    r1.show(); 
    Console.WriteLine("Area of r1: " + r1.area()); 
 
    Console.WriteLine(); 
 
    // create a rectange that is twice as big as r1 
    Rect r2 = r1.enlarge(2); 
 
    Console.Write("Dimensions of r2: "); 
    r2.show(); 
    Console.WriteLine("Area of r2 " + r2.area()); 
  } 
}// Проанализируйте код, объясните результаты 
 
using System;
 
class Rect
{
    public int width;
    public int height;
 
    public Rect(int w, int h)
    {
        width = w;
        height = h;
    }
 
    public int area()
    {
        return width * height;
    }
}
 
class UseRect
{
    public static void Main()
    {
        Rect r1 = new Rect(4, 5);
        Rect r2 = new Rect(7, 9);
 
        Console.WriteLine("Area of r1: " + r1.area());
 
        Console.WriteLine("Area of r2: " + r2.area());
 
    }
}// Проанализируйте код и объясните результаты 
  
using System; 
 
class Overload {  
  public void ovlDemo() {  
    Console.WriteLine("No parameters");  
  }    
  // Overload ovlDemo for one integer parameter.  
  public void ovlDemo(int a) {  
    Console.WriteLine("One parameter: " + a);  
  }    
  // Overload ovlDemo for two integer parameters.  
  public int ovlDemo(int a, int b) {  
    Console.WriteLine("Two parameters: " + a + " " + b);  
    return a + b; 
  }  
  
  // Overload ovlDemo for two double parameters.  
  public double ovlDemo(double a, double b) { 
    Console.WriteLine("Two double parameters: " + 
                       a + " "+ b);  
    return a + b;  
  }  
}  
  
class OverloadDemo {  
  public static void Main() {  
    Overload ob = new Overload();  
    int resI; 
    double resD;      
  
    // call all versions of ovlDemo()  
    ob.ovlDemo();   
    Console.WriteLine(); 
    ob.ovlDemo(2);  
    Console.WriteLine(); 
 
    resI = ob.ovlDemo(4, 6);  
    Console.WriteLine("Result of ob.ovlDemo(4, 6): " + 
                       resI);  
    Console.WriteLine(); 

    resD = ob.ovlDemo(1.1, 2.32);  
    Console.WriteLine("Result of ob.ovlDemo(1.1, 2.2): " + 
                       resD);  
  }  
} // Проанализируйте код и объясните результаты 
 
using System;
 
class IfDemo
{
    public static void Main()
    {
        int a, b, c;
 
        a = 2;
        b = 3;
 
        if (a < b) Console.WriteLine("a is less than b");
 
        // this won't display anything  
        if (a == b) Console.WriteLine("you won't see this");
 
        Console.WriteLine();
 
        c = a - b; // c contains -1 
 
        Console.WriteLine("c contains -1");
        if (c >= 0) Console.WriteLine("c is non-negative");
        if (c < 0) Console.WriteLine("c is negative");
 
        Console.WriteLine();
 
        c = b - a; // c now contains 1 
        Console.WriteLine("c contains 1");
        if (c >= 0) Console.WriteLine("c is non-negative");
        if (c < 0) Console.WriteLine("c is negative");
 
    }
}// Проанализируйте код и объясните результаты 
 
using System;
 
class IfDemo
{
    public static void Main()
    {
        int a, b, c;
 
        a = 2;
        b = 3;
 
        if (a < b) Console.WriteLine("a is less than b");
 
        // this won't display anything  
        if (a == b) Console.WriteLine("you won't see this");
 
        Console.WriteLine();
 
        c = a - b; // c contains -1 
 
        Console.WriteLine("c contains -1");
        if (c >= 0) Console.WriteLine("c is non-negative");
        if (c < 0) Console.WriteLine("c is negative");
 
        Console.WriteLine();
 
        c = b - a; // c now contains 1 
        Console.WriteLine("c contains 1");
        if (c >= 0) Console.WriteLine("c is non-negative");
        if (c < 0) Console.WriteLine("c is negative");
 
    }
}
 
 // Проанализируйте код и объясните результаты 
 
using System;
 
class ProdSum
{
    static void Main()
    {
        int prod;
        int sum;
        int i;
 
        sum = 0;
        prod = 1;
 
        for (i = 1; i <= 5; i++)
        {
            sum = sum + i;
            prod = prod * i;
        }
        Console.WriteLine("Sum is " + sum);
        Console.WriteLine("Product is " + prod);
 
    }
}// Проанализируйте код и объясните результаты 
 
using System;
 
class PreDemo
{
    public static void Main()
    {
        int x, y;
        int i;
 
        x = 1;
        Console.WriteLine("Series generated using y = x + ++x;");
        for (i = 0; i < 10; i++)
        {
 
            y = x + ++x; // prefix ++ 
 
            Console.WriteLine(y + " ");
        }
        Console.WriteLine();
 
    }
}// Проанализируйте код и объясните результаты 
 
using System;
 
class PostDemo
{
    public static void Main()
    {
        int x, y;
        int i;
 
        x = 1;
        Console.WriteLine("Series generated using y = x + x++;");
        for (i = 0; i < 10; i++)
        {
 
            y = x + x++; // postfix ++ 
 
            Console.WriteLine(y + " ");
        }
        Console.WriteLine();
    }
}// Проанализируйте код и объясните результаты 
 
// Create an implication operator in C#. 
using System;
 
class Implication
{
    public static void Main()
    {
        bool p = false, q = false;
        int i, j;
 
        for (i = 0; i < 2; i++)
        {
            for (j = 0; j < 2; j++)
            {
                if (i == 0) p = true;
                if (i == 1) p = false;
                if (j == 0) q = true;
                if (j == 1) q = false;
 
                int b = (!p | q)?1:0;
                Console.WriteLine(i + " " + j + " " + b);
 
                Console.WriteLine();
            }
        }
    }
}// Проанализируйте код и объясните результаты 
 
using System;
 
class LogicalFunction
{
    public static void Main()
    {
        for (int i = 0; i < 2; i++)
        {
            for (int j = 0; j < 2; j++)
            {
                int b = (i*j>0)?1:0;
                Console.WriteLine(i + " " + j + " " + b);
 
                Console.WriteLine();
            }
        }
    }
}// Проанализируйте код и объясните результаты 
 
using System;
 
class LogicalFunction
{
    public static void Main()
    {
        for (int i = 0; i < 2; i++)
        {
            for (int j = 0; j < 2; j++)
            {
                int b = (i+j>0)?1:0;
                Console.WriteLine(i + " " + j + " " + b);
 
                Console.WriteLine();
            }
        }
    }
}// Проанализируйте код и объясните результаты 
 
using System;
 
class Ladder
{
    public static void Main()
    {
        int num;
 
        for (num = 2; num < 12; num++)
        {
            if ((num % 2) == 0)
                Console.WriteLine("Smallest factor of " + num + " is 2.");
            else if ((num % 3) == 0)
                Console.WriteLine("Smallest factor of " + num + " is 3.");
            else if ((num % 5) == 0)
                Console.WriteLine("Smallest factor of " + num + " is 5.");
            else if ((num % 7) == 0)
                Console.WriteLine("Smallest factor of " + num + " is 7.");
            else
                Console.WriteLine(num + " is not divisible by 2, 3, 5, or 7.");
        }
    }
}// Проанализируйте код, исправьте ошибки, и объясните результаты 
 
using System;
 
class SwitchDemo
{
    public static void Main()
    {
        int i;
 
        for (i = 0; i < 10; i++)
            switch (i)
            {
                case 0:
                    Console.WriteLine("i is zero");
                case 1:
                    Console.WriteLine("i is one");
                case 2:
                    Console.WriteLine("i is two");
                case 3:
                    Console.WriteLine("i is three");
                case 4:
                    Console.WriteLine("i is four");
                default:
                    Console.WriteLine("i is five or more");
            }
 
    }
}// Проанализируйте код, исправьте ошибки, и объясните результаты 

using System;
 
class SwitchDemo
{
    public static void Main()
    {
        double i;
 
        for (i = 0; i < 10; i++)
            switch (i)
            {
                case 0:
                    Console.WriteLine("i is zero");
                    break;
                case 1:
                    Console.WriteLine("i is one");
                    break;
                case 2:
                    Console.WriteLine("i is two");
                    break;
                case 3:
                    Console.WriteLine("i is three");
                    break;
                case 4:
                    Console.WriteLine("i is four");
                    break;
                default:
                    Console.WriteLine("i is five or more");
            }
 
    }
}// Проанализируйте код, объясните результаты 
 
using System;
 
class SwitchDemo2
{
    public static void Main()
    {
        char ch;
 
        for (ch = 'A'; ch <= 'z'; ch++)
            switch (ch)
            {
                case 'A':
                case 'a':
                    Console.WriteLine("ch is A or a");
                    break;
                case 'B':
                case 'b':
                    Console.WriteLine("ch is B or b");
                    break;
                case 'C':
                case 'c':
                    Console.WriteLine("ch is C or c");
                    break;
                case 'D':
                case 'd':
                    Console.WriteLine("ch is D or d");
                    break;
                case 'E':
                case 'e':
                    Console.WriteLine("ch is E or e");
                    break;
                default:
                    Console.WriteLine(ch+" "+(int)ch);
                    break;
 
            }
    }
}// Проанализируйте код, объясните результаты 
 
using System;
 
class forDemo
{
    public static void Main()
    {
        int i, j;
        bool done = false;
 
        for (i = 0, j = 100; !done; i++, j--)
        {
 
            if (i * i >= j) done = true;
 
            Console.WriteLine("i, j: " + i + " " + j);
        }
 
    }
}// Проанализируйте код, объясните результаты 
using System;
 
class ForVar
{
    public static void Main()
    {
        int sum = 0;
        int fact = 1;
 
        for (int i = 1; i <= 5; i++)
        {
            sum += i;  // i is known throughout the loop 
            fact *= i;
        }
 
        Console.WriteLine("sum is " + sum);
        Console.WriteLine("fact is " + fact);
    }
}// Проанализируйте код, объясните результаты 
 
using System;
 
class WhileDemo
{
    public static void Main()
    {
        int num;
        int mag;
 
        num = 435679;
        mag = 0;
 
        Console.WriteLine("Number: " + num);
 
        while (num > 0)
        {
            mag++;
            num = num / 10;
        };
 
        Console.WriteLine("Magnitude: " + mag);
    }
}// Проанализируйте код, объясните результаты 
 
using System;
 
class Power
{
    public static void Main()
    {
        int e;
        int result;
 
        for (int i = 0; i < 11; i++)
        {
            result = 1;
            e = i;
 
            while (e > 0)
            {
                result *= 2;
                e--;
            }
 
            Console.WriteLine("2 to the " + i +
                               " power is " + result);
        }
    }
}// Проанализируйте код, объясните результаты 
 
using System;
 
class Building
{
    public int floors;    // number of floors 
    public int area;      // total square footage of building 
    public int occupants; // number of occupants 
 
    // Display the area per person.  
    public int areaPerPerson()
    {
        return area / occupants;
    }
}
 
// Use the return value from areaPerPerson().   
class BuildingDemo
{
    public static void Main()
    {
        Building house = new Building();
        int areaPP; // area per person 
 
        // assign values to fields in house 
        house.occupants = 4;
        house.area = 75;
        house.floors = 2;
 
        // obtain area per person for house 
        areaPP = house.areaPerPerson();
 
        Console.WriteLine("house has:\n  " +
                          house.floors + " floors\n  " +
                          house.occupants + " occupants\n  " +
                          house.area + " total area\n  " +
                          areaPP + " area per person");

    }
}// Проанализируйте код, объясните результаты 
 
using System;
class Building
{
    public int floors;    // number of floors 
    public int area;      // total square footage of building 
    public int occupants; // number of occupants 
 
    // Display the area per person.  
    public int areaPerPerson()
    {
        return area / occupants;
    }
    /* Return the maximum number of occupants if each 
       is to have at least the specified minimum area. */
    public int maxOccupant(int minArea)
    {
        return area / minArea;
    }
}
// Use maxOccupant(). 
class BuildingDemo
{
    public static void Main()
    {
        Building house = new Building();
        Building office = new Building();
 
        // assign values to fields in house 
        house.occupants = 4;
        house.area = 150;
        house.floors = 2;
 
        // assign values to fields in office 
        office.occupants = 25;
        office.area = 420;
        office.floors = 2;
 
        Console.WriteLine("Maximum occupants for house if each has " +
                          20 + " square metre: " +
                          house.maxOccupant(20));
 
        Console.WriteLine("Maximum occupants for office if each has " +
                          10 + " square metre: " +
                          office.maxOccupant(10));
    }
}// Проанализируйте код, объясните результаты 
 
using System;
 
class Building
{
    public int floors;    // number of floors 
    public int area;      // total square footage of building 
    public int occupants; // number of occupants 

    public Building(int f, int a, int o)
    {
        floors = f;
        area = a;
        occupants = o;
    }
 
    // Display the area per person.  
    public int areaPerPerson()
    {
        return area / occupants;
    }
 
    /* Return the maximum number of occupants if each 
       is to have at least the specified minum area. */
    public int maxOccupant(int minArea)
    {
        return area / minArea;
    }
}
 
// Use the parameterized Building constructor. 
class BuildingDemo
{
    public static void Main()
    {
        Building house = new Building(2, 2500, 4);
        Building office = new Building(3, 4200, 25);
 
        Console.WriteLine("Maximum occupants for house if each has " +
                          300 + " square feet: " +
                          house.maxOccupant(300));
 
        Console.WriteLine("Maximum occupants for office if each has " +
                          300 + " square feet: " +
                          office.maxOccupant(300));
    }