循环链表解决约瑟夫环问题

 1 /**

 2  * 循环链表求解约瑟夫环问题

 3  **/

 4 #include <iostream>

 5 #include <cstdlib>

 6 using namespace std;

 7 

 8 /**

 9  * 数据结构

10  **/

11 typedef struct DanamicList {

12     int id;

13     struct DanamicList* next;

14 } List;

15 

16 /**

17  * 创建循环链表

18  **/

19 List* InitList(int numCount) {

20     if(numCount <= 0) {

21         cout << "Value is invalid!!!\n";

22         exit(-1);

23     }

24     List *head = head = new List;

25     if(!head) {

26         cout << "Alloc memory failed!!!\n";

27         exit(-1);

28     }

29 

30     head->id = 1;

31     List *pre = head;

32     for(int index = 1; index < numCount; ++index) {

33         List *temp = new List;

34         if(!temp) {

35             cout << "Alloc memory failed!!!\n";

36             exit(-1);

37         }

38         temp->id = index + 1;

39         temp->next = NULL;

40         pre->next = temp;

41         pre = temp;

42     }

43     pre->next = head;

44 

45     return head;

46 }

47 

48 /**

49  * 求解约瑟夫环问题

50  **/

51 void josephus(List* head, int number) {

52     int count = 0, flag = 0;

53     List *pre = head, *del = NULL;

54 

55     while(pre->next != head)

56         pre = pre->next;

57     do {

58         ++count;

59         if(number != count)

60             pre = pre->next;

61         else {

62             count = 0;

63             del = pre->next;

64             cout << del->id << "\t";

65             pre->next = pre->next->next;

66             if (pre != pre->next)

67                 delete del;

68         }

69         if(pre == pre->next)

70             ++flag;

71     } while(flag - (number + 1));             // 数学关系

72     delete pre;

73 }

74 

75 /**

76  * 主函数

77  **/

78 int main(void) {

79     List *head = NULL;

80     int totalPeople = 0, outNumber = 0;

81     cout << "请输入总数和出队密码：";

82     cin >> totalPeople;

83     cin >> outNumber;

84 

85     head = InitList(totalPeople);             // 创建循环链表

86     josephus(head, outNumber);                // 求解约瑟夫环

87 

88     return 0;

89 }