static object Solve()
{
var(n, qc) = Read2();
var c = Read();
var qs = new bool[qc]
.Select((_, id) => { var a = Read(); return(id, l: a[0] - 1, r: a[1] - 1); })
.GroupBy(q => q.r)
.ToDictionary(g => g.Key, g => g.ToArray());
// 各色に対して、最も右のインデックス
var ris = Array.ConvertAll(new bool[n + 1], _ => - 1);
var set = new IndexedSet <int>();
var counts = new int[qc];
for (int i = 0; i < n; i++)
{
if (ris[c[i]] != -1)
{
set.Remove(ris[c[i]]);
}
ris[c[i]] = i;
set.Add(i);
if (qs.ContainsKey(i))
{
foreach (var(id, l, _) in qs[i])
{
var li = set.GetFirstIndex(x => x >= l);
counts[id] = set.Count - li;
}
}
}
return(string.Join("\n", counts));
}
