codeforce Sereja and Suffixes(简单题)

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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 a1a2...an. The boy cannot sit and do nothing, he decided to study an array. Sereja took a piece of paper and wrote out m integers l1, l2, ..., lm (1 ≤ li ≤ n). For each number li he wants to know how many distinct numbers are staying on the positions lili + 1, ..., n. Formally, he want to find the number of distinct numbers among ali, 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 each li.

Input

The first line contains two integers n and m (1 ≤ n, m ≤ 105). The second line contains n integers a1a2...an (1 ≤ ai ≤ 105) — the array elements.

Next m lines contain integers l1, l2, ..., lm. The i-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
以前绝对做过类似的题目,用一个数组来保存是否有过相同的地方,只是这题有更优解,(而且自己也看过这种解的代码),所以只是用了一个memset()函数,就在第11组数据里面TLE了一下,实在不应该。
AC掉的代码:
#include<stdio.h>#include<string.h>int n,m;int A[100005], B[100005], pass[100005];int l;int main(){    while(scanf("%d %d", &n, &m)!=EOF)    {        int i, j;        for(i=1; i<=n; ++i)            scanf("%d", &A[i]);        int sum=0;        for(i=n; i>=1; --i)        {            if(B[A[i]]==0)            {                ++sum;                B[A[i]]=1;            }            pass[i]=sum;        }        for(j=1; j<=m; ++j)        {            scanf("%d", &l);            printf("%d\n", pass[l]);        }    }    return 0;}

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