1)
const
    t = 18 * 60 + 30;

var
    s: string;
    i, n, k, d1, d2: integer;

begin
    readln(n);
    for i := 1 to n do
    begin
        readln(d1, d2);
        if d1 * 60 + d2 < t then k := k + 1
    end;
    writeln(k);
end.

2)
var
    n, k: integer;

begin
    readln(n);
    while n 0 do
    begin
        if (n mod 5 = 0) or (n mod 7 = 0) then k := k + 1;
        readln(n);
    end;
    writeln(k);
end.