import std.stdio,
       std.conv,
       std.string,
       std.range,
       std.algorithm;

void main()
{
    auto N = readln.strip.to!int;

    auto ans = 1;
    foreach (i; 1 .. 28)
    {
        if ((1UL << i) >= N)
            break;
        ans++;
    }
    ans.writeln;
}