#include
#include
using namespace std;
int findmid(int a, int b, int c, int d);
int intxt[401];
ofstream outfile;
int main() {
 ifstream infile;
 outfile.open(“D:\123\output.txt”);
 infile.open(“D:\123\input.txt”);
 if (!infile.is_open()||!outfile.is_open()) {
  cout << “文件打开失败”;
  return 0;
 } 
 for (int i = 0; !infile.eof(); i++) {//读取数组
  infile >> intxt[i];
 }
 int n = intxt[0];
 findmid(1, n, n + 1, 2 * n);
 infile.close();
 outfile.close();
 return 0;
}
//递归求中位数算法
int findmid(int a, int b, int c, int d) {
 if (a == b) { //划分至每个数组只有一个数时
  if (intxt[b] < intxt[c]) {
   outfile << intxt[b];
   cout << intxt[b];
  }
  else {
   outfile << intxt[c];
   cout << intxt[c];
  }
  return 0;
 }
 //比较两个数组中位数
 int x = (a + b) / 2;
 int y = (c + d) / 2;
 int x1 = intxt[x];
 int y1 = intxt[y];
 if (x1 > y1) {
  findmid(a, x, c + b – x, d);
 }
 else if (x1 < y1) {
  findmid(a + d – y, b, c, y);
 }
 else {
  outfile << x1;
  cout << x1;
 }
 return 0;
}