cannot convert 'ListNode*' to 'ListNode**' C-CodePudding

#include <bits/stdc  .h>

using namespace std;

struct ListNode {
    int val;
    ListNode *next;
    ListNode() : val(0), next(nullptr) {}
    ListNode(int x) : val(x), next(nullptr) {}
    ListNode(int x, ListNode *next) : val(x), next(next) {}
};

void printList(ListNode *head) {
    ListNode *curr = head;
    while (curr != NULL) {
        cout << curr->val;
        curr = curr->next;
    }
}

int main() {
    ListNode *head[5];
    ListNode *node;
    head[0] = new ListNode(1,NULL);
    for (int  i = 1; i < 5; i  ) {
        head[i] = new ListNode(i   1, head[i - 1]);
    }

    node = head[5]; //cannot convert 'ListNode*' to 'ListNode**'
    printList(node);

    return 0;
}

How should i pass last node as single pointer to function ? i am not able to convert node in double pointer to single pointer variable.

CodePudding user response：

Like Armin pointed out in the comments, you are referencing the array beyond the range.

if you replace

node = head[5];

with

node = head[4];  //this is the 5th element of the array.

you would probably get the output you were expecting.