Cod sursa(job #695984)
Utilizator | Data | 28 februarie 2012 16:06:36 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 40 |
Compilator | fpc | Status | done |
Runda | Arhiva educationala | Marime | 0.32 kb |
var f:text;i,n,j,k:longint;a:array[1..2000000]of boolean;
begin
assign(f,'ciur.in');reset(f);
read(f,n);
close(f);
for i:=2 to n do
a[i]:=true;
for i:=2 to n div 2 do
for j:=2 to n div i do
a[i*j]:=false;
k:=0;
for i:=2 to n do
if a[i]=true then k:=k+1;
assign(f,'ciur.out');rewrite(f);
write(f,k);
close(f);
end.