Var
i,j,n,Fi,Fj:longint;
Fi1,Fn:extended;
k:integer;
F:array[-2001..2001] of extended;
Begin
  Readln(i,Fi,j,Fj,n);
  F[0]:=0; F[1]:=1;

  for k:=2 to 2001 do
  F[k]:=F[k-1]+F[k-2];

  for k:=-1 downto -2001 do
  F[k]:=F[k+2]-F[k+1];

  Fi1:=((Fj-F[j-i-1]*Fi)/F[j-i]);
  Fn:=(F[n-i]*Fi1+F[n-i-1]*Fi);
  writeln(round(Fn));
End.

Why WA#16?

Edited by author 06.11.2008 13:26