Cod sursa(job #289785)
Utilizator | Data | 26 martie 2009 23:31:36 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 100 |
Compilator | fpc | Status | done |
Runda | aa | Marime | 0.41 kb |
program ciur;
var f:text;
a:array[1..2000001] of byte;
n,i,j,nr:longint;
begin
assign(f,'ciur.in');
reset(f);
read(f,n);
close(f);
nr:=0;
for i:=2 to n do
if a[i]=0 then begin
inc(nr);
j:=0;
while (j+1)*i<=n do begin
inc(j);
a[i*j]:=1;
end;
end;
assign(f,'ciur.out');
rewrite(f);
write(f,nr);
close(f);
end.