题目1004：Median

最新推荐文章于 2021-10-21 14:47:55 发布

原创最新推荐文章于 2021-10-21 14:47:55 发布 · 710 阅读

0 ·

CC 4.0 BY-SA版权

ACM 专栏收录该内容

14 篇文章

订阅专栏

本文介绍了一种算法，该算法用于找到两个已排序整数序列的中位数。通过将两个序列合并并排序，然后选取中间元素作为中位数。示例展示了如何输入两个序列并输出它们的中位数。

题目描述：

Given an increasing sequence S of N integers, the median is the number at the middle position. For example, the median of S1={11, 12, 13, 14} is 12, and the median of S2={9, 10, 15, 16, 17} is 15. The median of two sequences is defined to be the median of the non-decreasing sequence which contains all the elements of both sequences. For example, the median of S1 and S2 is 13.
Given two increasing sequences of integers, you are asked to find their median.

输入：

    Each input file may contain more than one test case.
    Each case occupies 2 lines, each gives the information of a sequence. For each sequence, the first positive integer N (≤1000000) is the size of that sequence. Then N integers follow, separated by a space.
    It is guaranteed that all the integers are in the range of long int.

输出：

For each test case you should output the median of the two given sequences in a line.

样例输入：

4 11 12 13 145 9 10 15 16 17

样例输出：

#include <iostream>
#include <algorithm>

using namespace std;

bool cmp(const int &a, const int &b)
{
    if(a > b)
        return 0;
    if(a < b)
        return 1;
}
int main()
{
    int num1,num2;
    while(cin >> num1)
    {
        int *arr1 = new int[num1];
        for(int i = 0; i < num1; i++)
        {
            cin >> arr1[i];
        }

        cin >>num2;
        int *arr2 = new int[num2+num1];
        for(int i = 0; i < num1; i++)
        {
            arr2[i] = arr1[i];
        }
        for(int i = 0; i <num2; i++)
        {
            cin >> arr2[i + num1];
        }
        sort(arr2,arr2+(num1+num2),cmp);
        cout << arr2[(num1 + num2 + 1)/2-1] << endl;

    }
}