P5055

const double alp = 0.2;
const double delp = 0.8281;

int merge(const int u, const int v) {
	if(sz[u] <= s * delp && sz[v] <= s * delp) 
	if(sz[u] >= sz[v]) 
		if(sz[l] >= alp * s)
	else 
		if(sz[r] >= alp * s)
}