我試圖在C. N叉樹的實現當運行它,我得到以下錯誤:中止陷阱6的malloc
sibling(1143,0x7fff7e925000) malloc: *** error for object 0x7f946b4032c8: incorrect checksum for freed object - object was probably modified after being freed.
*** set a breakpoint in malloc_error_break to debug
Abort trap: 6
我不能確定是什麼原因造成的錯誤。正如它所說,我似乎正在寫給一個被釋放的對象。但在我的代碼中,我沒有釋放任何分配的內存。我對c很陌生,非常困惑。我試着用gdb進行調試,它說錯誤是由printTree()引起的。主要調用我遞歸地嘗試打印樹的地方。希望你能幫助我理解這個問題:-)。
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
typedef struct {
char *name;
unsigned int utility;
unsigned int probability;
} Child;
typedef struct {
unsigned int level;
unsigned int player;
unsigned int nChildren;
Child *children;
} Data;
typedef struct sNaryNode{
Data *data;
struct sNaryNode *kid;
struct sNaryNode *sibling;
} NaryNode;
NaryNode* createNode(Data data){
NaryNode *newNaryNode = malloc(sizeof (NaryNode*));
newNaryNode->sibling = NULL;
newNaryNode->kid = NULL;
newNaryNode->data = &data;
return newNaryNode;
}
NaryNode* addSibling(NaryNode* n, Data data){
if(n == NULL) return NULL;
while(n->sibling)
n = n->sibling;
return (n->sibling = createNode(data));
}
NaryNode* addChild(NaryNode* n, Data data){
if(n == NULL) return NULL;
else if(n->kid)
return addSibling(n->kid, data);
else
return (n->kid = createNode(data));
}
void printTree(NaryNode* n) {
if(n == NULL) return;
if(n->sibling) {
printf("%u %u %u %u %u %s", n->data->level, n->data->player, n->data->nChildren, n->data->children[0].probability, n->data->children[0].utility, n->data->children[0].name);
printTree(n->sibling);
}
else if(n->kid) {
printf("%u %u %u %u %u %s", n->data->level, n->data->player, n->data->nChildren, n->data->children[0].probability, n->data->children[0].utility, n->data->children[0].name);
printTree(n->kid);
}
else {
printf("The tree was printed\n");
}
}
int main(void) {
NaryNode *root = calloc(1, sizeof(NaryNode));
Data data;
data.level = 1;
data.player = 1;
data.nChildren = 2;
data.children = calloc(data.nChildren, sizeof data.nChildren);
data.children[0].probability = 50;
data.children[0].utility = 1;
data.children[0].name = "Kom med det første tilbud (anchor)";
data.children[1].probability = 50;
data.children[1].utility = 1;
data.children[1].name = "Afvent modspilleren kommer med første tilbud";
*root = *createNode(data);
int i = 0;
for(i=0; i<root->data->nChildren; i++) {
addChild(root, data);
}
printTree(root);
}
線'data.children =釋放calloc(data.nChildren,的sizeof data.nChildren);'不有道理。 – 2016-12-04 14:04:10
'data.children = calloc(data.nChildren,sizeof data.nChildren)'你確定要sizeof data.nChildren嗎?嘗試'sizeof * data.children'。 – Stargateur
.........'sizeof(Child)' –