coderforce --B. Sereja and Suffixes

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B. Sereja and Suffixes
time limit per test
1 second
memory limit per test
256 megabytes
input
standard input
output
standard output

Sereja has an array a, consisting of n integers a1,a2, ..., an. The boy cannot sit and do nothing, he decided to study an array. Sereja took a piece of paper and wrote outm integers l1, l2, ..., lm(1 ≤ li ≤ n). For each numberli he wants to know how many distinct numbers are staying on the positionsli,li + 1, ...,n. Formally, he want to find the number of distinct numbers amongali, ali + 1, ..., an.?

Sereja wrote out the necessary array elements but the array was so large and the boy was so pressed for time. Help him, find the answer for the described question for eachli.

Input

The first line contains two integers n andm (1 ≤ n, m ≤ 105). The second line containsn integers a1,a2, ..., an(1 ≤ ai ≤ 105) — the array elements.

Next m lines contain integers l1, l2, ..., lm. Thei-th line contains integer li (1 ≤ li ≤ n).

Output

Print m lines — on the i-th line print the answer to the number li.

Sample test(s)
Input
10 101 2 3 4 1 2 3 4 100000 9999912345678910
Output
6666654321
题意:找出输入数组中l后面位置不同的数的个数,满水的一道,可是我竟然没有1A,就是太差劲了。。用一个记录数组arr来记录该数字之前有没有出现过,然后在result数组里面保存不同数字的个数,然后直接查询也就可以了。。我是从后面开始记录的,从前面也可以,不过那就要用最后减去前面那个。。都差不多。。贴下代码:
#include<stdio.h>int arr[100005],sav[100005];int res[100005];int main(){    int n,m;int temp;    for(int i=0;i<100005;i++)    {arr[i]=0;     res[i]=0;     sav[i]=0;    }    scanf("%d%d",&n,&m);    for(int i=0;i<n;i++)    {        scanf("%d",&temp);        sav[i]=temp;    }    res[n-1]=1;    arr[sav[n-1]]=1;    for(int i=n-2;i>=0;i--)    {       if(arr[sav[i]]==0)       {           res[i]=res[i+1]+1;           arr[sav[i]]=1;       }       else       res[i]=res[i+1];    }   for(int i=0;i<m;i++)   {       scanf("%d",&temp);       printf("%d\n",res[temp-1]);   }    return 0;}


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