Форум программистов [Powered by Invision Power Board]

Код

program Method_Gaussa;

uses crt;

const  N=4;

var    A:array[1..N,1..N] of real;
       b:array[1..N] of real;
       x:array[1..N] of real;
       i,j:integer;

{///////////////////////////////////////////////////////////////////////////}
procedure Vvod;
begin
    writeln ('Vvedite elementi rasshirennoi matrici koefficientov:');
    writeln;
    for i:=1 to N do
        begin
        for j:=1 to N do
            begin
            write('a[' ,i:2, ',' ,j:2, ']=');
            readln(A[i,j]);
            end;
        write('b[' ,i:2, ']=');
        readln(b[i]);
        end;
end;

{///////////////////////////////////////////////////////////////////////////}
procedure vivod_A;
begin
     for i:=1 to N do
         for j:=1 to N do
             begin
             writeln;
             for j:=1 to N do
             write (A[i,j]:8);
             end;
         writeln;
         writeln;
end;

{///////////////////////////////////////////////////////////////////////////}
procedure Reformation;
var k,r:integer;
    mx,c,M:real;
begin
    for k:=1 to N do
        begin
        mx:=abs(A[k,k]);
        r:=k;
        for i:=k+1 to N do
            if abs(A[i,k])>mx then
               begin
               mx:=abs(A[i,k]);
               r:=i;
               end;
        for j:=1 to N do
            begin
            c:=A[k,j];
            A[k,j]:=A[r,j];
            A[r,j]:=c;
            end;
        c:=b[k];
        b[k]:=b[r];
        b[r]:=c;
        for i:=k+1 to N do
            begin

            M:=(A[i,k]/A[k,k]);
            for j:=k to N do
            A[i,j]:=A[i,j]-(M*A[k,j]);
            b[i]:=b[i]-(M*b[k]);
            end;
        end;
end;

{////////////////////////////////////////////////////////////////////////////}
procedure Reverse;
var s:real;
begin
    if A[N,N]=0 then
        if b[N]=0
               then writeln('Besconechnoe mnojestvo reshenii')
               else writeln('Reshenii net')
       else for i:=N downto 1 do
               begin
                   s:=0;
                   for j:=i+1 to N do
                   s:=s+A[i,j]*x[j];
               x[i]:=(b[i]-s)/A[i,i];
               writeln('x[' ,i:2, ']=',x[i]);
               end;

end;

{////////////////////////////////////////////////////////////////////////////}
begin
clrscr;

      Vvod;

      Reformation;

      {Vivod_A;}

      Reverse;

readln;
end.