CodeForces 275C 贪心

CodeForces 275C 贪心2014-04-10 csdn accelerator_A k-multiple free set is a set of integers where there is no pair of integers where one is equal to another integer multiplied by k. That is, there are no two integers x and y （x<y） from the set, such that y=x·k.

You"re given a set of n distinct positive integers. Your task is to find the size of it"s largest k-multiple free subset.

Input

The first line of the input contains two integers n and k （1≤n≤105,1≤k≤109）. The next line contains a list of n distinct positive integers a1,a2,...,an （1≤ai≤109）.

All the numbers in the lines are separated by single spaces.

Output

On the only line of the output print the size of the largest k-multiple free subset of {a1,a2,...,an}.

Sample InputInput

6 22 3 6 5 4 10

Output

Hint

In the sample input one of the possible maximum 2-multiple free subsets is {4, 5, 6}.

题意：给定集合，就出不存在y = k*x的子集。

贪心：从小到大选过去，如果选到，则他的k *x 不能选，用set标记下来

代码：

#include <stdio.h>#include <string.h>#include <set>#include <algorithm>using namespace std;int n, k, i, j;long long num[100005], ans;set<long long> save;int main（） {ans = 0;scanf（"%d%d", &n, &k）;for （i = 0; i < n; i ++） {scanf（"%lld", &num[i]）;}sort（num, num + n）;for （i = 0; i < n; i ++） {if （save.count（num[i]） == 0） {ans ++;save.insert（num[i] * k）;}}printf（"%lld
", ans）;return 0;}