codeforces 166C Median 中位数

#113 div2

题意：给n个数的序列，问最少添加多少个数字，使得序列的中位数是m？

暴力排序，首先注意如果序列里没有m那么添加一个m是必须的，然后就是对于每个m，判断其前后分别有多少个数字，通过计算要加几个数字来把当前数字推到中位数位置

#include <iostream>
#include <cstring>
#include <cstdio>
#include <algorithm>
#define rep(i, j, k) for (int i = j; i <= k; i++)

using namespace std;

int n, p, a[1000];

int main ()
{
	cin >> n >> p;
	rep (i, 1, n)
		scanf ("%d", &a[i]);
	int have = 0;
	rep (i, 1, n)
		have |= (a[i] == p);
	if (have == 0)
		a[++n] = p;
	sort (a + 1, a + 1 + n);
	int l = 0, r = 0, ans = 0x7fffffff;
	rep (i, 1, n)
		if (a[i] == p)
		{
			l = i;
			break;
		}
	for (int i = n; i >= 1; i--)
		if (a[i] == p)
		{
			r = i;
			break;
		}
	if (a[(n + 1) / 2] == p)
	{
		cout << 0 + (have == 0)<< endl;
		return 0;
	}
	rep (i, l, r)
	{
		int left = i - 1, right = n - i;
		//printf ("%d == %d %d\n", i, left, right);
		if (left < right)
			ans = min (ans, right - left - 1);
		else
			ans = min (ans, left - right);
	}
	cout << ans + (have == 0) << endl;
}