with Ada.Text_IO; use Ada.Text_IO;
procedure Hello is
begin
    Put_Line ('Hello, world!');
end Hello;

with Ada.Text_IO; use Ada.Text_IO;
procedure Show_Sum is
    A, B, Sum : Integer;
begin
    A := 5;
    B := 7;
    Sum := A + B;
    Put_Line (Integer'Image(Sum));
end Show_Sum;

with Ada.Text_IO; use Ada.Text_IO;
procedure Array_Sum is
    type Array_Type is array (1 .. 5) of Integer;
    Array_Var : Array_Type := (2, 4, 6, 8, 10);
    Sum : Integer := 0;
begin
    for I in Array_Var'Range loop
        Sum := Sum + Array_Var(I);
    end loop;
    Put_Line (Integer'Image(Sum));
end Array_Sum;

with Ada.Text_IO; use Ada.Text_IO;
procedure Simple_Task is
    task T is
        entry Start;
    end T;
    task body T is
    begin
        accept Start;
        Put_Line ('Task T is running.');
    end T;
begin
    T.Start;
end Simple_Task;

with Ada.Text_IO; use Ada.Text_IO;
procedure Simple_Class is
    type Class_Type is tagged record
        Data : Integer := 0;
    end record;
    procedure Show (Obj : Class_Type) is
    begin
        Put_Line (Integer'Image(Obj.Data));
    end Show;
    Obj : Class_Type;
begin
    Obj.Data := 5;
    Show (Obj);
end Simple_Class;

with Ada.Text_IO; use Ada.Text_IO;
procedure Advanced_Code is
    type Matrix_Type is array (1 .. 3, 1 .. 3) of Integer;
    Matrix : Matrix_Type := ((1, 2, 3), (4, 5, 6), (7, 8, 9));
begin
    for I in 1 .. 3 loop
        for J in 1 .. 3 loop
            Put (Integer'Image(Matrix(I, J)) & ' ');
        end loop;
        New_Line;
    end loop;
end Advanced_Code;