Question

我在尝试打印* p值时遇到此问题，而p指向列表的nodo（显然我想打印nodo.info值）这是代码，希望你理解：

struct nodo {
    int info;
    struct nodo *prec;
    struct nodo *succ;
} ;
typedef struct nodo nodo;

int main (void) {     // just declaring my 3 nodos
    struct nodo *p;

    struct nodo anodo;
    struct nodo bnodo;
    struct nodo cnodo;

    anodo.info = 200;
    anodo.prec = NULL;
    anodo.succ = NULL;

    bnodo.info = 22;
    bnodo.prec = NULL;
    bnodo.succ = NULL;

    cnodo.info = 2000;
    cnodo.prec = NULL;
    cnodo.succ = NULL;

    anodo.succ = &bnodo;    
    bnodo.prec = &anodo;
    bnodo.succ = &cnodo;    
    cnodo.prec = &bnodo;

    p = &anodo;

    printf("\n%d\n", checklist (p));       // calling function 

    return 0;
}

nodo *checklist (struct nodo *p) {
    int j=0;

    while (p != NULL) {
        if (p->info >= p->succ->info) {     //if first element is major or same than next
            p=p->succ;

        } else {
            while (p != NULL) {
                if (p->info >= p->succ->info) {     //same
                    p=p->succ;
                    j++;
                } else {
                    p = NULL;
                }
            }
        }
    } 

    while (j != 0) {
        p = p->prec;     //used a counter to get back to the first nodo in wich next was less than prev
        j--;
    }

    return p;
}

随时询问任何细节

Answer 1

p = checklist (p);
if (p) 
   printf("\n%d\n", p->info);

Answer 2

您需要返回nodo.info然后

int checklist (struct nodo *p) {
    int j=0;

    while (p != NULL) {
        /* avoid this p->succ->info */
        if (p->info >= p->succ->info) {     //if first element is major or same than next
            p = p->succ;
        } else {  
            while (p != NULL) {
                if (p->info >= p->succ->info) {     //same
                    p = p->succ;
                    j++;
                } else { 
                    p = NULL;                        
                }          
            }
        }
    }

    while (j != 0) { p = p->prec;     //used a counter to get back to the first nodo in wich next was less than prev
        j--;
    }
    return p->info;
}

或主要

int info
struct nodo *found;

found = checklist(p);
if (found != NULL)
    printf("\n%d\n", found->info);

打印指针值

2 个答案: