Help with pasting strings to a .txt file

[hoandini]

Hello,

I have some trouble with my homework and I can't find the problem.

my code:

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "input3.h"


int main(int argc, char **argv) {
   if (argc < 3) {
        printf("Aufruf: %s <anzahl> <bundesland>\n", argv[0]);
        printf("Beispiel: %s 100 Bayern\n", argv[0]);
        printf("Klein-/Großschreibung beachten!\n");
        exit(1);
    }
    int anzahl = atoi(argv[1]);
    char *bundesland = argv[2];   


    
    char staedte[MAX_LAENGE_ARR][MAX_LAENGE_STR];
    char laender[MAX_LAENGE_ARR][MAX_LAENGE_STR];
    int bewohner[MAX_LAENGE_ARR];  


    int len = read_file("staedte.csv", staedte, laender, bewohner);


char *result[len];
int j, i=0;
int diff = 1;
int min =1;






for (j=0; j<len; j++)  {
    result[j] = (char*) malloc(100*sizeof(char));
diff = strcmp(bundesland, laender[j]);
min = bewohner[j] - anzahl;






 if (diff ==0 && 0 <= min)  {
 snprintf(result[i], 100, "Die Stadt %s hat %d Einwohner.", staedte[j], bewohner[j]);
    i++;
                }  
}
                             
write_file(result, len);
 free(*result);
}

you open the code with ./<program name> <number> <country> and it pastes on a .txt file every city of the country + its population but only those whose population is higher than the entered number.

My problem is that there are multiple empty lines and I don't know what to do.

[Salem]

Indenting your code would be a start.

> write_file(result, len);
But the number of valid records found is given by 'i', not 'len'.

> free(*result);
This only frees the first result you malloc'ed, not all of them.

[hoandini]

Thank you so much, found the problem now .