#include #include #define MOVEMAX 16 typedef struct s_board { char walked; short pos; } Board; typedef struct s_node { Board b; struct s_node *next; } Node; typedef struct s_queue { Node *front; Node *rear; } Queue; Node *createNode(char walked,short pos,Node *next); Queue *iniQueue(void); void freeNode(Node *node); void freeQue(Queue *que); char isEmpty(Queue *que); char enqueue(Queue *que,char walked,short pos); Board dequeue(Queue *que, char *err); void iniBoard(Board *b); char walkNum(short a); char walking(short n,Queue *que); int main(void) { short n; char ans; Queue *que; char err; Board b; scanf("%hd",&n); iniBoard(&b); que = iniQueue(); enqueue(que,b.walked,b.pos); ans = walking(n,que); printf("%d\n",ans); freeQue(que); return 0; } Node *createNode(char walked,short pos,Node *next) { Node *node = malloc(sizeof(Node)); if (node == NULL) { perror("node malloc"); exit(1); } node->b.walked = walked; node->b.pos = pos; node->next = next; return node; } Queue *iniQueue(void) { Queue *que = malloc(sizeof(Queue)); if (que == NULL) { perror("que malloc"); exit(1); } que->front = NULL; que->rear = NULL; return que; } void freeNode(Node *node) { while (node != NULL) { Node *tmp = node->next; free(node); node = tmp; } return; } void freeQue(Queue *que) { freeNode(que->front); free(que); return; } char isEmpty(Queue *que) { if (que->front == NULL) return 1; else return 0; } char enqueue(Queue *que,char walked,short pos) { Node *node = createNode(walked,pos,NULL); if (node == NULL) return 1; if (isEmpty(que) == 1) { que->front = node; que->rear = node; } else { que->rear->next = node; que->rear = node; } return 0; } Board dequeue(Queue *que, char *err) { Board b; if (isEmpty(que)) { *err = 1; return b; } Node *node = que->front; b = node->b; que->front = node->next; free(node); if (que->front == NULL) que->rear = NULL; *err = 0; return b; } void iniBoard(Board *b) { b->walked = 1; b->pos = 1; return; } char walkNum(short a) { int i=0; while (1) { i += a % 2; if (a<=1) break; a = a / 2; } return i; } char walking(short n,Queue *que) { Board b; char err; char wNum; int ans; ans = -1; while (1) { b = dequeue(que,&err); if (err==1) break; if (b.walked > MOVEMAX) break; if (b.pos == n) { ans = b.walked; break; } wNum = walkNum(b.pos); if (b.pos - wNum > 0) { err = enqueue(que,b.walked+1,b.pos-wNum); if (err == 1) { perror("enqueue -"); break; } } if (b.pos + wNum <= n) { err = enqueue(que,b.walked+1,b.pos+wNum); if (err == 1) { perror("enqueue +"); break; } } } return ans; }