poj1012 约瑟夫环

/*
Time:2019.10.31
Author: Goven
type：约瑟夫环问题 
ref:https://www.cnblogs.com/yu-chao/archive/2011/05/29/2062276.html
*/
#include<iostream>
using namespace std;

bool test(int k, int m) {
    int n = 2 * k;
    int j = 0;
    for (int i = 0; i < k; i++) {//进行k次报数 
        j = (j + m - 1) % (n - i);
        if (j < k) return false;
    }
    return true;
}
int main()
{
    int Joseph[14] = {0};
    for (int i = 1; i < 14; i++) {//表示人数的一半 
        int j = i + 1;//表示报数
        while(1) {
            if (test(i, j)) {
                Joseph[i] = j;
                break;
            }
            
            if (test(i, j + 1)) {
                Joseph[i] = j + 1;
                break;
            }
            
            j = i + j + 1;//Att:为何能够替代成j++? 见ref
        } 
    }
    
    int k;
    while (cin >> k && k) {
        cout << Joseph[k] << endl;
    }   
    return 0;
}