Mai intai trebuie sa te autentifici.
Cod sursa(job #576896)
Utilizator | Data | 9 aprilie 2011 16:49:33 | |
---|---|---|---|
Problema | Fractii | Scor | 100 |
Compilator | fpc | Status | done |
Runda | Arhiva de probleme | Marime | 0.52 kb |
var v:array [1..1000000] of longint;
i, j, n:longint;
sum:int64;
f, g:text;
begin
assign (f, 'fractii.in'); reset (f);
assign (g, 'fractii.out'); rewrite (g);
read (f, n);
for i := 1 to n do v[i]:=i;
i:=2;
while i <= n do
begin
if v [i] = i then
begin
j:=i;
while j <= n do
begin
v[j]:=v[j]- v[j] div i;
j:=j+i;
end;
end;
i:=i+1;
end;
for i := 1 to n do sum := sum + v[i];
sum:=sum*2-1;
writeln (g, sum);
close (f); close (g);
end.