Question

Looking forward to help…I need to read two strings from text files and store them into two separate arrays. I’ve searched, and got many codes, one of which worked, so I tried to modify it to read two strings. Here is my code:

int main(){
int i = 0;
int BUFSIZE = 1000;
char* words[20];
char* words2[20];
FILE *fp = fopen("input1.txt", "r");
FILE *fp2 = fopen("input2.txt", "r");
if (fp == 0){
    fprintf(stderr, "Error while opening");
    return 0;
}
words[i] = (char*)malloc(BUFSIZE);
words2[i] = (char*)malloc(BUFSIZE);
while (fgets(words[i], BUFSIZE, fp)) {
    i++;
    words[i] = (char*)malloc(BUFSIZE);
} 
while (fgets(words2[i], BUFSIZE, fp2)) {
    i++;
    words2[i] = (char*)malloc(BUFSIZE);
} 
printf("Output: \n");
srand(time(NULL));
int j = rand()%i;
int k = (j+1)%i;
fflush(stdout);
printf("%d - %s %d -%s", j, words[j], k, words[k]); 

int x;
for(x = 0; x<i; x++)
   free(words[x]);
   free(words2[x]);
scanf("%d", x);
fclose(fp);
fclose(fp2);
return 0;
}

But it won’t work.Anyone knows why? Thank you!

Answer 1

Reset i = 0 before second loop and enbrace your free(x) code in curly braces

int main()
{
    int i = 0;
    int BUFSIZE = 1000;
    char* words[20];
    char* words2[20];
    FILE *fp = fopen("input1.txt", "r");
    FILE *fp2 = fopen("input2.txt", "r");
    if (fp == 0){
        fprintf(stderr, "Error while opening");
        return 0;
    }
    words[i] = (char*)malloc(BUFSIZE);
    words2[i] = (char*)malloc(BUFSIZE);
    while (fgets(words[i], BUFSIZE, fp)) {
        i++;
        words[i] = (char*)malloc(BUFSIZE);
    } 

    // reset i back to zero
    i = 0; 
    while (fgets(words2[i], BUFSIZE, fp2)) {
        i++;
        words2[i] = (char*)malloc(BUFSIZE);
    } 

    printf("Output: \n");
    srand(time(NULL));
    int j = rand()%i;
    int k = (j+1)%i;
    fflush(stdout);
    printf("%d - %s %d -%s", j, words[j], k, words[k]); 

    int x;
    for(x = 0; x<i; x++){
       free(words[x]);
       free(words2[x]);
    }
    scanf("%d", x);
    fclose(fp);
    fclose(fp2);
    return 0;
}