Pointer to pointer to Struct [closed] - c

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I'm trying to do a C program that receives Strings and store them into structs dynamically, and after the passing strings part, I will show witch of them was written most. But I'm having trouble coding the pointers to pointers to structs. I'm trying to do something like the image that I draw here.
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
struct Word{
char* palavra;
int aparicoes;
} ;
struct word createWord(char* str){
struct Word *newWord = malloc(sizeof(struct Word));
assert(newWord != NULL);
newWord->palavra = strdup(str);
newWord->aparicoes = 1;
return newWord;
}
int main (){
char* tempString;
struct Word** lista;
int triggrer = 1;
int i = 0;
while (triggrer == 1)
{
scanf("%s", tempString);
if (strcmp(tempString , "fui") == 0)
triggrer = 0;
else
{
while(*(&lista+i*sizeof(lista)) != NULL){
i++;
}
if(i == 0){
lista = malloc(sizeof(struct Word));
}
else{
lista = (struct Word*) realloc(lista, sizeof(struct Word) + i*sizeof(struct Word));
}
}
}
return 0;
}

Answer 1

There is no allocation of the pointers anywhere.
You need something like this:
lista = (struct Word**) malloc(sizeof(struct Word*));
*lista = NULL;
the above allocate one pointer to pointer to struct. the pointer to struct itself is null.
Now, not sure what you want to achieve by
while(*(&lista+i*sizeof(lista)) != NULL){
i++;
}
If you want to find the end of you array of pointers, presuming that the last pointer is NULL, then this is the code to do it:
while (*(lista + i) != NULL) i++;
Also, there are some typos in the code. This would compile and work. But I personally, recommend to use normal array of pointers (i.e. just keep the size of the array in another variable).
struct Word{
char* palavra;
int aparicoes;
} ;
struct Word * createWord(char* str){
struct Word *newWord = (struct Word *)malloc(sizeof(struct Word));
newWord->palavra = strdup(str);
newWord->aparicoes = 1;
return newWord;
}
int main()
{
char tempString[1024];
struct Word** lista;
int triggrer = 1;
int i = 0;
lista = (struct Word**)malloc(sizeof(struct Word*));
*lista = NULL;
while (triggrer == 1)
{
scanf("%s", tempString);
if (strcmp(tempString , "fui") == 0)
triggrer = 0;
else
{
while(*(lista+i) != NULL){
i++;
}
lista = (struct Word**)realloc(lista, (i+1) * sizeof(struct Word*));
*(lista+i) = createWord(tempString);
*(lista+i+1) = NULL;
}
}
return 0;
}