### BUGGY CODE ###

#参考https://qiita.com/takayg1/items/c811bd07c21923d7ec69

#####segfunc#####
def segfunc(x, y):
    return x+y
#################

#####ide_ele初期値#####
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 ※区間注意
        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

#%%

def function():
    N, Q = map(int, input().split())
    c = list(map(int, input().split()))
    lrs = [list(map(lambda x:int(x)-1, input().split())) for i in range(Q)]
    
    for i in range(len(lrs)):
        lrs[i] = [lrs[i][0], lrs[i][1], i]
    
    right_edge = [-1]*(N+1)
    seg = SegTree([0]*(N+1), segfunc, ide_ele)

    lrs = sorted(lrs, key = lambda x:x[1])
    order_num = 0
    answer = [0]*(Q)
    for i, c_o in enumerate(c):
        if right_edge[c_o] >= 0:
            seg.update(right_edge[c_o], 0)
        right_edge[c_o] = i
        seg.update(i, 1)
        
        for j in range(N):
            if order_num >= Q:
                break
            if lrs[order_num][1] == i:
                answer[lrs[order_num][2]] = [order_num,seg.query(lrs[order_num][0],lrs[order_num][1]+1)]
                order_num += 1
            else:
                break
    
    for i in range(len(answer)):
        print(answer[i][1])
        
if __name__ == '__main__':
    function()

### FIXED CODE ###

import sys
import numpy as np

read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines

Bsize = 700

def Mo_argsort(LR):
    L = LR[:, 0]
    R = LR[:, 1]
    key1 = L // Bsize
    key2 = np.where(key1 & 1, -R, R)
    key = (key1 << 32) + key2
    return np.argsort(key)

def main(A, LR):
    N = len(A)
    Q = len(LR)
    ind = Mo_argsort(LR)
    count = np.zeros(N + 1, np.int64)
    ans = 0

    def add(x):
        nonlocal ans
        if not count[x]:
            ans += 1
        count[x] += 1

    def rem(x):
        nonlocal ans
        count[x] -= 1
        if not count[x]:
            ans -= 1

    answers = np.empty(Q, np.int64)
    nl, nr = 0, 0
    for i in ind:
        l, r = LR[i]
        l -= 1
        # 区間 [l, r) に対する計算
        while nl > l:
            nl -= 1
            add(A[nl])
        while nr < r:
            add(A[nr])
            nr += 1
        while nl < l:
            rem(A[nl])
            nl += 1
        while nr > r:
            nr -= 1
            rem(A[nr])
        #  答を求めて ans[i] に格納する
        answers[i] = ans
    return answers

if sys.argv[-1] == 'ONLINE_JUDGE':
    import numba
    from numba.pycc import CC
    i4 = numba.int32
    i8 = numba.int64
    cc = CC('my_module')

    def cc_export(f, signature):
        cc.export(f.__name__, signature)(f)
        return numba.njit(f)

    Mo_argsort = cc_export(Mo_argsort, (i8[:,:],))
    main = cc_export(main, (i8[:], i8[:, :]))
    cc.compile()

from my_module import main

N, Q = map(int, readline().split())
A = np.array(readline().split(), np.int64)
LR = np.array(read().split(), np.int64).reshape(Q, 2)

ans = main(A, LR)
print('\n'.join(map(str, ans.tolist())))