Putting information from a char array into a Dynamically created array

Question

I'm trying to pass information from a char string that's been tokenized using " ." as the set.
Turn those characters into integers using atoi()
Then send the values into dynamically allocated memory

I know the theory, I know how it's supposed to work, but I can't get the right syntax to make it work!

The second part, after I declare *Malloc_Array_ptr* is where I run into trouble. So far, I've used the Malloc Pointer exactly how I'd use a regular array pointer, and I'm not getting any results on my printf test.

Can't find info that makes sense to me over google, I'm going crazy over this. I think I'm real close to figuring it out, I just need a nudge in the right direction >.<

Thank you! :)

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define SIZE 10
#define MIN_SIZE 2


void StrInput(char str[], int maxChars);

int main(int argc, char *argv[])
{
  char Array[SIZE], *Array_ptr = strtok(Array, " .");
  StrInput(Array, SIZE);
  int i=1, *temp = Array_ptr;

//Strok initialized in order to use NULL next sequence. 
//Temp stores the pointer in it's original form, before it gets butchered by strtok
  while (Array_ptr != NULL)
  {
     Array_ptr = strtok(NULL, " .");
     i++;
  }
//Above code finds the number of tokens strtok worked on, and stores it as i.

//Dynamically Creates the array which can hold exactly the amount of tokens (i)
  int *Malloc_Array_ptr = (int*)malloc(i* sizeof(int)), hold;

  i=0;
  while (Array_ptr != NULL)
  {
     temp = strtok(NULL, " .");
     hold = atoi(temp);
     Malloc_Array_ptr[i] = hold;
     i++;
  }

  printf("Show me the money: %s \n", Malloc_Array_ptr);
  system("PAUSE");  
  return 0;
}


/*----------------------------------------------------------------------*/
void StrInput(char str[], int maxChars)
{
   int i=0, str_lenght;
   while ((str[i] = getchar()) != '\n')
      i++;
   str[i+1]='\0';


   if (i>maxChars || i<MIN_SIZE)
      {
         printf("Your sumbition dosn't fit the size criteria.\n");
         printf("Please reenter:\n\n");
         StrInput(str, maxChars);
      }
}

Vaughn Cato · Accepted Answer · 2013-04-28 18:55:25Z

2

This is problematic:

char Array[SIZE], *Array_ptr = strtok(Array, " .");

You are declaring the array, then trying to use strtok on the uninitialized array. You probably meant to do this:

char Array[SIZE], *Array_ptr = 0;
StrInput(Array, SIZE);
Array_ptr = strtok(Array, " .");

answered Apr 28, 2013 at 18:55

Vaughn Cato

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1 Comment

Farstride Over a year ago

I worked around the balancing act, but in the end it was just a minor error and didn't change the nature of the real problem :(

BLUEPIXY · Accepted Answer · 2013-04-28 22:51:21Z

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define SIZE 10
#define MIN_SIZE 2


void StrInput(char str[], int maxChars);

int main(int argc, char *argv[]){
    char Array[SIZE], *Array_ptr, *strwk;
    StrInput(Array, SIZE);
    int i=0;

    strwk=strdup(Array);//strtok would change the string. so make a copy.
    Array_ptr=strtok(strwk, " .");
    while (Array_ptr != NULL){
        ++i;//countup element
        Array_ptr = strtok(NULL, " .");
    }

    int *Malloc_Array_ptr = (int*)malloc(i* sizeof(int));

    i=0;
    strcpy(strwk, Array);
    Array_ptr = strtok(strwk, " .");
    while (Array_ptr != NULL){
        Malloc_Array_ptr[i] = atoi(Array_ptr);
        ++i;
        Array_ptr = strtok(NULL, " .");
    }
    free(strwk);
    int j;
    //check print
    for(j=0;j<i;++j)
        printf("%d ", Malloc_Array_ptr[j]);
    printf("\n");
//  printf("Show me the money: %s \n", Malloc_Array_ptr);//Malloc_Array_ptr isn't (char*).
    system("PAUSE");  
    return 0;
}

/*----------------------------------------------------------------------*/
void StrInput(char str[], int maxChars){
    int i=0, ch;//str_lenght: unused
    int InputOver = 0;

    printf("input numbers :");
    for(i=0;(ch = getchar()) != '\n';++i){
        if(i > maxChars -1){//-1: for EOS(\0)
            i = maxChars - 1;
            InputOver = !InputOver;//true
            break;
        }
        str[i]=(char)ch;
    }
    str[i]='\0';

    if (InputOver || i<MIN_SIZE){
        printf("Your sumbition dosn't fit the size criteria.\n");
        printf("Please reenter:\n\n");
        while('\n'!= ch){//clear input
            ch = getchar();
        }
        StrInput(str, maxChars);
    }
}

Works exactly as hoped, I'll be studying how this works so I understand and create my own! Thank you! +all the well deserved rep I can give =D

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