program z1;

type mas = array[1..100] of real;

function calc_sum_masses( p: mas; count: integer ): real;
  var i: integer;
  var sum: real;
begin
  i := 1;
  sum := 0;
  while i <= count do
  begin
    sum := sum + p[i];
    i := i + 1;
  end;
  calc_sum_masses := sum;
end;

function calc_coord( p: mas; c: mas; sum_masses: real; count: integer ): real;
  var i: integer;
  var sum: real;
begin
  i := 1;
  while i <= count do
  begin
    sum := sum + p[i]*c[i];
    i := i + 1;
  end;
  calc_coord := sum / sum_masses;
end;

var
  p: mas;
  c: array[1..3] of mas;
  count: integer;
  sum_masses: real;
begin
  count := 2;

  p[1] := 20;
  p[2] := 20;

  //x
  c[1][1] := 0;
  c[1][2] := 0;

  //y
  c[2][1] := 0;
  c[2][2] := 0;

  //z
  c[3][1] := 0;
  c[3][2] := 10;

  sum_masses := calc_sum_masses( p, count );

  writeln( 'U: ', calc_coord(p, c[1], sum_masses, count) );
  writeln( 'V: ', calc_coord(p, c[2], sum_masses, count) );
  writeln( 'W: ', calc_coord(p, c[3], sum_masses, count) );

end.