循环链表实现约瑟夫环

数据结构老师在课上提到的 故事背景很有意思 所以我就做了一下

///循环链表实现






#include<iostream>
using namespace std;


typedef struct node{
    int data;
    node *next;/// struct
}node;


node *createlist(int n){
    if(n<1){
        cout << "Error!" << endl;
        return NULL;
    }
    node *head = new node;
    node *p;
    head->data = 1;
    p = head;


    for(int i=1; i<n; i++){
        node *s = new node;
        s->data = i+1;
        p->next = s;
        s->next = head;
        p = s;
    }
    return head;
}


node *removelist(node *p){
    node *next = p->next;
    delete p;
    return next;
}
int joseph(int n, int beg, int loop){
    if(beg > n){
        cout << "start can't be bigger than number\n";
        return -1;
    }
    if(loop < 1){
        cout << "loop at least is 1\n";
        return -1;
    }
    node *one = createlist(n);
    node *p = one;
    for(int i=1; i<beg; i++){
        p = p->next;
    }
    while(p->next!=p){
        for(int j=1; j<=loop-2; j++){
            p = p->next;
        }
        node *s = p->next;
        p ->next = s->next;
        p = s->next;
        delete s;


    }
    return p->data;
}


int main(int argc, char const *argv[]) {
    int c = joseph(10, 1, 3);
    cout << c << endl;
    return 0;
}





#include<iostream>
using namespace std;

typedef struct node{
    int data;
    node *next;/// struct
}node;

node *createlist(int n){
    if(n<1){
        cout << "Error!" << endl;
        return NULL;
    }
    node *head = new node;
    node *p;
    head->data = 1;
    p = head;

    for(int i=1; i<n; i++){
        node *s = new node;
        s->data = i+1;
        p->next = s;
        s->next = head;
        p = s;
    }
    return head;
}

node *removelist(node *p){
    node *next = p->next;
    delete p;
    return next;
}
int joseph(int n, int beg, int loop){
    if(beg > n){
        cout << "start can't be bigger than number\n";
        return -1;
    }
    if(loop < 1){
        cout << "loop at least is 1\n";
        return -1;
    }
    node *one = createlist(n);
    node *p = one;
    for(int i=1; i<beg; i++){
        p = p->next;
    }
    while(p->next!=p){
        for(int j=1; j<=loop-2; j++){///   比如 1 2 3 这三个人中间只间隔一个人 所以减2
            p = p->next;
        }
        node *s = p->next;
        p ->next = s->next;
        p = removelist(s);
    }
    return p->data;
}

int main(int argc, char const *argv[]) {
    int c = joseph(10, 1, 3);
    cout << c << endl;
    return 0;
}