### BUGGY CODE ###

import sys

sys.setrecursionlimit(10**7)
def I(): return int(sys.stdin.readline().rstrip())
def MI(): return map(int,sys.stdin.readline().rstrip().split())
def LI(): return list(map(int,sys.stdin.readline().rstrip().split()))  #空白あり
def LI2(): return list(map(int,sys.stdin.readline().rstrip()))  #空白なし
def S(): return sys.stdin.readline().rstrip()
def LS(): return list(sys.stdin.readline().rstrip().split())  #空白あり
def LS2(): return list(sys.stdin.readline().rstrip())  #空白なし


N,Q = MI()
c = LI()
n = len(set(c))
A = list(set(c))
d = {}
for i in range(n):
    d[A[i]] = i
for i in range(N):
    c[i] = {d[c[i]]}


def seg_func(x,y):
    return x|y


unit = set([])


class SegTree:  # モノイドに対して適用可能、Nが2冪でなくても良い
    def __init__(self,N,seg_func,unit):
        self.N = N
        self.func = seg_func
        self.unit = unit
        self.tree = [self.unit]*(2*self.N)
    def build(self,init_value):  # 初期値を[N,2N)に格納
        for i in range(self.N):
            self.tree[i+self.N] = init_value[i]
        for i in range(self.N-1,0,-1):
            self.tree[i] = self.func(self.tree[i << 1],self.tree[i << 1 | 1])
    def set_val(self,i,x):  # i番目(0-index)の値をxに変更
        i += self.N
        self.tree[i] = x
        while i > 1:
            i >>= 1
            self.tree[i] = self.func(self.tree[i << 1],self.tree[i << 1 | 1])
    def fold(self,L,R):  # [L,R)の区間取得
        L += self.N
        R += self.N
        vL = self.unit
        vR = self.unit
        while L < R:
            if L & 1:
                vL = self.func(vL,self.tree[L])
                L += 1
            if R & 1:
                R -= 1
                vR = self.func(self.tree[R],vR)
            L >>= 1
            R >>= 1
        return self.func(vL,vR)


seg = SegTree(N,seg_func,unit)
seg.build(c)

for i in range(Q):
    l,r = MI()
    print(len(seg.fold(l-1,r)))



### FIXED CODE ###

def main():
    import sys
    def MI():
        return map(int, sys.stdin.readline().rstrip().split())
    def LI():
        return list(map(int, sys.stdin.readline().rstrip().split()))  # 空白あり

    N,Q = MI()
    c = [0] + LI()
    lr = []
    for i in range(Q):
        l,r = MI()
        lr.append((i,l,r))

    from operator import itemgetter

    lr = sorted(lr,key=itemgetter(2))  # 右端rでソート
    a = 0
    d = {}  # d[i] = 玉iが現れた最も右の位置
    ANS = [0]*Q


    class BIT():
        def __init__(self, init_value):
            self.n = len(init_value)
            self.tree = [0] * (self.n + 1)
            for i in range(1, self.n + 1):
                x = init_value[i - 1]
                while i <= self.n:
                    self.tree[i] += x
                    i += i & (-i)

        def update(self, i, x):  # i(1-index)番目の値を+x
            while i <= self.n:
                self.tree[i] += x
                i += i & (-i)
            return

        def query(self, i):  # 1番目からi(1-index)番目までの和を返す
            res = 0
            while i > 0:
                res += self.tree[i]
                i -= i & (-i)
            return res


    bit = BIT([0]*N)  # 最も右に現れた玉の位置を管理
    for i in range(1,N+1):
        if not c[i] in d.keys():
            d[c[i]] = i
            bit.update(i,1)
        else:
            bit.update(d[c[i]],-1)
            d[c[i]] = i
            bit.update(i, 1)
        while a <= Q-1 and lr[a][2] == i:
            j,l,r = lr[a]
            ANS[j] = bit.query(r)-bit.query(l-1)
            a += 1

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


if __name__ == '__main__':
    main()