Do you known test?I got wa 2,but I think that my program is right)

It's my code:
var
F:array[0..1000000] of longint;
I,j,mi,n:longint;
Begin
Read(n);
F[0]:=0;
F[1]:=1;
F[2]:=2;
For i:=3 to n do
Begin
Mi:=100000;
For j:=1 to trunc(sqrt(i)) do
If mi>f[i-j*j] then mi:=f[i-j*j];
F[i]:=mi+1;
End;
Writeln(f[i]);
End.

Writeln(f[i]); = undefined behaviour

first of all, try f[n], not f[i]

You are a superman!!!!!!!!!!!!Thanks)