Cod sursa(job #695951)
Utilizator | Data | 28 februarie 2012 15:51:01 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 30 |
Compilator | fpc | Status | done |
Runda | Arhiva educationala | Marime | 0.32 kb |
var f,g:text;i,n:longint;a:array[1..2000000]of boolean;
k,j:integer;
begin
assign(f,'ciur.in');reset(f);
assign(g,'ciur.out');rewrite(g);
read(f,n);
for i:=1 to n do
a[i]:=true;
for i:=2 to n do
for j:=2 to n div i do
a[i*j]:=false;
for i:=2 to n do
if a[i]=true then k:=k+1;
write(g,k);
close(f);
close(g);
end.