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arrayscansi-c

Fill an array in C


I have a question on filling an array with values in C. I have a string that I want to split into an array of new strings each 14 'sections' long.

int main(int argc , char *argv[])
{
char string[]="50 09 00 00 98 30 e0 b1 0d 01 00 00 00 00 4f 09 00 00 98 30 c6 b1 0d 01 01 01 01 50 09 00 00 98 30 e0 b1 0d 01 00 00 00 00 4f 09 00 00 98 30 c6 b1 0d 01 01 01 01";

char delim[] = " ";
char *result = NULL;
char *strArray[1440] = {0};
int i = 0;
result = strtok(string, " ");

while (result) 
{
 strArray[i] = result;
 result = strtok( NULL, delim );
 i++;
}

// Now I have each 'section' of the original string in strArray[xx]

int z = 1022;
int c;
char arr[5000];
char *finalarr[100] = {0};
char buff[100];
int l = 0;

for(c=0;c<z;++c) 
{
  strcat(arr,strArray[c]);
  if (c % 14 == 13)
  {
     // print the value so far for check, this gives an output of 28 chars 
     puts(arr);
     // copy value of arr to buff
     ret = sprintf(buff,"%s", arr);
     // copy value of buff to instance of finalarr
     finalarr[l] = buff;
     // empty arr
     strcpy(arr," ");
    l++;
  }
}

// both have the same value (last value of arr)
printf("finalarr1 = %s\n",finalarr[1]);
printf("finalarr20 = %s\n",finalarr[20]);
}

Perhaps I'm trying to solve it in a too complex way (I hope). Anyway some directions to help would be highly appreciated.


Solution

  • #include <stdio.h>
    #include <string.h>
    
    int main(int argc , char *argv[])
    {
        int i;
        int fcount=0;
        int acount=0;
        char string[]="50 09 00 00 98 30 e0 b1 0d 01 00 00 00 00 4f 09 00 00 98 30 c6 b1 0d 01 01 01 01 50 09 00 00 98 30 e0 b1 0d 01 00 00 00 00 4f 09 00 00 98 30 c6 b1 0d 01 01 01 01";
        char *finalarr[100];
        char arr[29]="\0";
        for (i=0;i<(strlen(string));i++)
        {
            if ((i+1)%3!=0)
            {
                strncpy(&arr[acount],&string[i],1);
                acount++;
                if (acount==28)
                {
                    acount=0;
                    arr[29]="\0";
                    finalarr[fcount]=strdup(arr);
                    fcount++;
                }
    
            }
        }
        printf("finalarr1 = %s\n",finalarr[0]);
        printf("finalarr1 = %s\n",finalarr[1]);
        printf("finalarr1 = %s\n",finalarr[2]);
        return 0;
    }
    

    result:

    finalarr1 = 500900009830e0b10d0100000000
    finalarr1 = 4f0900009830c6b10d0101010150
    finalarr1 = 0900009830e0b10d01000000004f