bzoj1013

裸的高斯消元不多说

var a:array[0..12,0..12] of double;
    b:array[0..12] of double;
    p,i,j,k,n:longint;
    x:double;

procedure swap(var a,b:double);
  var c:double;
  begin
    c:=a;
    a:=b;
    b:=c;
  end;

procedure gauss;
  begin
    for i:=1 to n do
    begin
      p:=i;
      for j:=i to n do
        if abs(a[p,i])<abs(a[j,i]) then p:=j;
      if p<>i then
      begin
        for j:=1 to n+1 do
          swap(a[p,j],a[i,j]);
      end;
      for j:=i+1 to n do
        if a[j,i]<>0 then
        begin
          for k:=n+1 downto i do
            a[j,k]:=a[j,k]-a[i,k]*a[j,i]/a[i,i];
        end;
    end;
    for i:=n downto 1 do
    begin
      for j:=i+1 to n do
        a[i,n+1]:=a[i,n+1]-a[j,n+1]*a[i,j];
      a[i,n+1]:=a[i,n+1]/a[i,i];
    end;
  end;

begin
  readln(n);
  for i:=1 to n do
    read(b[i]);
  for i:=1 to n do
  begin
    for j:=1 to n do
    begin
      read(x);
      a[i,j]:=(x-b[j])*2;
      a[i,n+1]:=a[i,n+1]+sqr(x)-sqr(b[j]);
    end;
  end;
  gauss;
  for i:=1 to n do
  begin
    write(a[i,n+1]:0:3);
    if i<>n then write(' ');
  end;
  writeln;
end.