循环赛日程表问题（分治法）

问题描述及代码参考：http://blog.csdn.net/wly_2014/article/details/51388263

代码部分：

//2018_02_25
//循环赛日程问题
//==========================================
#include <iostream>
#include <vector>

using namespace std;
//实现函数
void Table(vector<vector<int>> &vec)
{
    if (vec.size() == 0)
        return;
    size_t s = vec.size();  //size_t的range一般大于int
    int k = 0;
    while (s = s >> 1)
    {
        k++;
    }
    vec[0][0] = 1;
    vec[0][1] = 2;
    vec[1][0] = 2;
    vec[1][1] = 1;

    for (int i = 2; i <= k; i++)
    {
        int length = 1 << i;
        int half = length >> 1;
        //左下角的子表中项为左上角子表对应项加half = 2^(i-1)
        for (int row = 0; row < half; row++)
        {
            for (int col = 0; col < half; col++)
            {
                vec[row + half][col] = vec[row][col] + half;
            }
        }
        //右上角的子表等于左下角子表
        for (int row = 0; row < half; row++)
        {
            for (int col = 0; col < half; col++)
            {
                vec[row][col + half] = vec[row + half][col];
            }
        }
        //右小角子表等于左上角子表
        for (int row = 0; row < half; row++)
        {
            for (int col = 0; col < half; col++)
            {
                vec[row + half][col + half] = vec[row][col];
            }
        }
    }
}
//主函数
int main(void)
{
    cout << "共有2 ^ k 个选手参加比赛 ， 输入k(k > 0)：" << endl;
    int k;
    do
    {
        cin >> k;
    } while ((k < 0) || (k > 31));
    int s = 1 << k;  //总共s个选手
    vector <vector <int> > vec(s, vector<int>(s, 0));  //初始化表格，初始值为0

    Table(vec);

    for (size_t i = 0; i < vec.size(); i++)
    {
        for (size_t j = 0; j < vec[i].size(); j++)
            cout << vec[i][j] << " ";
        cout << endl;
    }
    system("pause");
    return 0;
}

结果如下：