private int BinSearch(int a, int b, int need, int M, PersistentPartialUnionFind uf)
{
int L = -1, R = M;
while (R - L > 1)
{
int mid = L + R >> 1;
int x = uf.Root(a, mid);
int y = uf.Root(b, mid);
int num = uf.NumElements(x, mid);
if (num < need && x != y)
{
num += uf.NumElements(y, mid);
}
if (num >= need)
{
R = mid;
}
else
{
L = mid;
}
}
return(R);
}
private int BinSearch(int a, int b, int need, int M, PersistentPartialUnionFind uf)
{
int L = -1, R = M;
while (R - L > 1)
{
int mid = L + R >> 1;
int num = uf.NumElements(a, mid) + (uf.Same(a, b, mid) ? 0 : uf.NumElements(b, mid));
if (num >= need)
{
R = mid;
}
else
{
L = mid;
}
}
return(R);
}