PAT甲级1085

1085. Perfect Sequence (25)

时间限制

300 ms

内存限制

65536 kB

代码长度限制

16000 B

判题程序

Standard

作者

CAO, Peng

Given a sequence of positive integers and another positive integer p. The sequence is said to be a "perfect sequence" if M <= m * p where M and m are the maximum and minimum numbers in the sequence, respectively.

Now given a sequence and a parameter p, you are supposed to find from the sequence as many numbers as possible to form a perfect subsequence.

Input Specification:

Each input file contains one test case. For each case, the first line contains two positive integers N and p, where N (<= 10⁵) is the number of integers in the sequence, and p (<= 10⁹) is the parameter. In the second line there are N positive integers, each is no greater than 10⁹.

Output Specification:

For each test case, print in one line the maximum number of integers that can be chosen to form a perfect subsequence.

Sample Input:

10 82 3 20 4 5 1 6 7 8 9

Sample Output:

8

#include<iostream>#include<cstdio>#include<string>#include<vector>#include<algorithm>using namespace std;int main(){int N;long long p;cin >> N >> p;vector<long long> v;long long t;for (int i = 0; i < N; i++){cin >> t;v.push_back(t);}sort(v.begin(), v.end());int len = 0;for (int i = 0; i < N; i++){for (int j = len+i; j < N; j++)//利用上次计算的信息{if (v[i]*p < v[j])break;//该中断时中断，后续比较无用if (len < j - i + 1){len = j - i + 1;}}}cout << len;return 0;}