How to compare two strings, which(both of them) are stored in char double pointer?

Question

char ** magazine;
char ** ransom;
*magazine = malloc(sizeof(char*) * m);
for(int magazine_i = 0; magazine_i < m; magazine_i++){
   magazine[magazine_i] = (char *)malloc(10240 * sizeof(char));
   scanf("%s",magazine[magazine_i]);
}
*ransom = malloc(sizeof(char*) * n);
for(int ransom_i = 0; ransom_i < n; ransom_i++){
   ransom[ransom_i] = (char *)malloc(10240 * sizeof(char));
   scanf("%s",ransom[ransom_i]);
}

Now I want to compare the string stored in ransom to magazine. How it can be done? Please help

[Please see this discussion on why not to cast the return value of `malloc()` and family in `C`.](http://stackoverflow.com/q/605845/2173917). — Sourav Ghosh, Nov 02 '16 at 07:48
Read about [strcmp](http://en.cppreference.com/w/c/string/byte/strcmp) — Basile Starynkevitch, Nov 02 '16 at 07:48

score 2 · Answer 1 · answered Nov 02 '16 at 08:01

You can use strcmp in a loop:

for (i = 0; i < n; i++) {
    if (strcmp(magazine[i], ransom[i]) == 0) {
        ...
    }
}

But if (as the title suggests) ransom is declared as a pointer to pointer to char:

char **ransom;

you don't want the dereference operator *

*ransom = malloc(sizeof(char*) * n);

should be

ransom = malloc(sizeof(char*) * n);

How to compare two strings, which(both of them) are stored in char double pointer?

1 Answers1