Question

I’m trying code a simple homework at school and get the error Segmentation fault (core dumped) implementing a linked list in C++ in this way:

struct Word{
    string word;
    string meaning;
    Word * next;
};

struct dictionary{
    Word *head = NULL;
    int count;
}dict;

string addWord(string word, string meaning){
    Word *newWord = new Word;
    newWord -> word = word;
    newWord -> meaning = meaning;
    newWord -> next = dict.head;
    dict.head = newWord;
    dict.count++; 
}

I’m trying to add a word (node) when get the error, I can’t use c++ class because is a requieriment of a teacher, sincery thank for you help!

Answer 1

dict.count is never initialized. Given that your compiler can include default initializations in a struct definition, you should write int count = 0; where it is defined. This is not causing your segfault, probably, but you still need to fix it.

I suspect addWord failing to return a string, despite it having that as a return value, could be causing your segfault. This results in undefined behavior (which could crash). A compiler worth its salt would give you a fatal warning for writing the code you wrote. Change the return type of addWord to void. Like this:

void addWord(string word, string meaning)

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