import std.algorithm, std.container, std.conv, std.math, std.range, std.typecons, std.stdio, std.string;

auto rdsp(){return readln.splitter;}
void pick(R,T)(ref R r,ref T t){t=r.front.to!T;r.popFront;}
void readV(T...)(ref T t){auto r=rdsp;foreach(ref v;t)pick(r,v);}

const n = 10000001;

void main()
{
  uint seed; readV(seed);

  auto calc(uint m)
  {
    init(seed);
    auto c = 0;
    foreach (_; 0..n) {
      auto a = generate();
      if (a <= m) ++c;
    }
    return c;
  }

  auto bs = iota(uint.max).map!(m => calc(m)).assumeSorted;
  writeln(bs.lowerBound((n+1)/2).length);
}

uint x = 0, y = 1, z = 2, w = 3;

void init(uint seed)
{
  x = seed;
  y = 1;
  z = 2;
  w = 3;
}

uint generate()
{
  uint t = (x^(x<<11));
  x = y;
  y = z;
  z = w;
  w = (w ^ (w >> 19)) ^ (t ^ (t >> 8)); 
  return w;
}