# Original solution
import sys, heapq
input = sys.stdin.readline
n, q = map(int, input().split())
c = [int(x) - 1 for x in input().split()]


que = []
for i in range(q):
    l, r = map(int, input().split())
    heapq.heappush(que, (r-1, l-1, i))


bit = [0 for _ in range(n)]
#####segfunc#####
def segfunc(x, y):
    return x + y
#################

#####ide_ele#####
ide_ele = 0
#################

class SegTree:
    """
    init(init_val, ide_ele): 配列init_valで初期化 O(N)
    update(k, x): k番目の値をxに更新 O(logN)
    query(l, r): 区間[l, r)をsegfuncしたものを返す O(logN)
    """
    def __init__(self, init_val, segfunc, ide_ele):
        """
        init_val: 配列の初期値
        segfunc: 区間にしたい操作
        ide_ele: 単位元
        n: 要素数
        num: n以上の最小の2のべき乗
        tree: セグメント木(1-index)
        """
        n = len(init_val)
        self.segfunc = segfunc
        self.ide_ele = ide_ele
        self.num = 1 << (n - 1).bit_length()
        self.tree = [ide_ele] * 2 * self.num
        # 配列の値を葉にセット
        for i in range(n):
            self.tree[self.num + i] = init_val[i]
        # 構築していく
        for i in range(self.num - 1, 0, -1):
            self.tree[i] = self.segfunc(self.tree[2 * i], self.tree[2 * i + 1])

    def update(self, k, x):
        """
        k番目の値をxに更新
        k: index(0-index)
        x: update value
        """
        k += self.num
        self.tree[k] = x
        while k > 1:
            self.tree[k >> 1] = self.segfunc(self.tree[k], self.tree[k ^ 1])
            k >>= 1

    def query(self, l, r):
        """
        [l, r)のsegfuncしたものを得る
        l: index(0-index)
        r: index(0-index)
        """
        res = self.ide_ele

        l += self.num
        r += self.num
        while l < r:
            if l & 1:
                res = self.segfunc(res, self.tree[l])
                l += 1
            if r & 1:
                res = self.segfunc(res, self.tree[r - 1])
            l >>= 1
            r >>= 1
        return res

BIT = SegTree(bit, segfunc, ide_ele)
lastAppeared = [-1 for _ in range(n)]
ans = [None for _ in range(q)]
for i in range(n):
    if lastAppeared[c[i]] != -1:
        BIT.update(lastAppeared[c[i]], 0)
    lastAppeared[c[i]] = i
    BIT.update(i, 1)


    while len(que) > 0 and que[0][0] == i:
        r, l, x = heapq.heappop(que)
        ans[x] = BIT.query(l, r+1)

    if len(que) == 0:
        break

    
print(*ans, sep='\n')


# Optimized solution
import sys, heapq
input = sys.stdin.readline
n, q = map(int, input().split())
c = [int(x) - 1 for x in input().split()]

que = []
for i in range(q):
    l, r = map(int, input().split())
    que.append((l, r, i))



class SegTree(object):
    def __init__(self, n):
        self.BIT = [0] * (n + 1)
        self.num = n

    def sum(self, i):
        s = 0
        while i > 0:
            s += self.BIT[i]
            i -= i & (-i)
        return s

    def add(self, i, x):
        while i <= self.num:
            self.BIT[i] += x
            i += i & (-i)
    

que.sort(key=lambda x: -x[1])
ans = [None] * q
last = [-1] * n
BIT = SegTree(n)

for i in range(1, n+1):
    if last[c[i-1]] != -1:
        BIT.add(last[c[i-1]], -1)
    last[c[i-1]] = i
    BIT.add(i, 1)

    while que and que[-1][1] == i:
        l, r, x = que.pop()
        ans[x] = BIT.sum(r) - BIT.sum(l-1)

print(*ans, sep='\n')