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program p_bot(input,output);
const n=3;
type matrix=array[1..n,1..n] of real; {n$B9T(Bn$BNs$N9TNs$r:n@.(B}
vector=array[1..n] of real; {n$BNs$r:n@.(B}
var a : matrix;
b : vector;
box_a:array[1..n] of real;
box_b:array[1..n] of real;
m,i,j:integer;
L:real;
procedure pbot_2(I,J:integer);
begin
for i:=J to n do
begin
box_a[i]:=a[J,i];
a[J,i]:=a[I,i];
a[I,i]:=box_a[i];
end;
box_b[J]:=b[J];
b[J]:=b[I];
b[I]:=box_b[J];
end; { pbot_2 }
procedure pbot_1(var a:matrix; n:integer);
begin
for j:=1 to n-1 do
begin
i:=j;
L:=abs(a[j,j]);
while (i<=n) do
begin
if (L<abs(a[i,j])) then
begin
L:=abs(a[i,j]);
m:=i;
end;
i:=i+1;
end;
pbot_2(m,j);
writeln(L:5:0,m,j);
end;
end; { pbot_1 }
procedure pbot(var a:matrix; var b:vector);
var i,j,I:integer;
L:real;
begin
for j:=1 to n-1 do
begin
i:=j;
L:=abs(a[j,j]);
while (i<=n) do begin
if (L<abs(a[i,j])) then begin
L:=abs(a[i,j]);
I:=i;
end;
i:=i+1;
end;
for i:=j to n do begin
box_a[i]:=a[j,i];
a[j,i]:=a[I,i];
a[I,i]:=box_a[i]
end;
box_b[j]:=b[j];
b[j]:=b[I];
b[I]:=box_b[j];
writeln(L:5:0,I,j);
end;
end; { pbot_1 }
procedure make_matrix(var a : matrix);
begin
a[1,1] := 1; a[1,2] := -2; a[1,3] :=-1;
a[2,1] := 2; a[2,2] := -4; a[2,3] := 0;
a[3,1] := -1; a[3,2] := 1; a[3,3] := 5
end; { make_matrix }
procedure make_vector(var b : vector);
begin
b[1] := -6;
b[2] := -6;
b[3] := 16;
end; { make_vector }
begin
make_matrix(a);
make_vector(b);
pbot(a,b);
end.
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Last modified: 2000$BG/(B1$B7n(B20$BF|(B 13:51