Question

I am failing one of the tests cases for the trimArray function. The test that my function is failing is testing that when you get a toTrim array of  " ", it should return "" (an array of no characters). How do I incorporate that functionality into the function and where will it go in the C++ code?

Here's my function:

// The function trimArray() is given a pointer to a character array that
// is NULL terminated called toTrim. This function is to remove any space characters
// that exist between the last non-space character and the NULL character in the toTrim array.
// Example, the following character string "This text " should be trimmed
// (or altered) to be "This text". The trimmed array is put in the array
// pointed to by the newArray pointer. Assume that the array pointed to by newArray
// is the same length as the toTrim array. If there are no spaces to trim a copy of
// the toTrim array should be made to the newArray.If the toTrim array has no characters
// then the newArray should have no cahracters(a null termination only).
void trimArray(const char *toTrim, char *newArray)
{
   //Initialization of the length variable to 0
   int length = 0;
   //Integer Index Variable (i)
   int i;
   //Integer Index Variable (j), initialized to 0
   int j = 0;

   //For loop gonig through the array toTrim to find the NULL character aka the length of the array
   for (i = 0; toTrim[i] != '\0'; i++)
   {
       //Incrementation of length + 1 each time a character other than the NULL character is found
       length++;
   }
  
   //For loop gonig through the array toTrim to find all of the characters that are not spaces
   //Starts at the last index of the array, and goes down by one each time
   //As long as i >= 0
   for (i = length - 1; i >= 0; i--)
   {
       //If condition setting all the non-space elements of the array equal to the values of another index
       //No space = character
       if (toTrim[i] != ' ')
       {
           //Set the current index to the j variable
           j = i;
           break;
       }
   }
  
   //For loop going through the arrays newArray and toTrim at index i setting the values equal until j
   for (i = 0; i <= j; i++)
   {
       //All characters from the toTrim Array are put into the newArray
       newArray[i] = toTrim[i];
   }
   //Adding a NULL character to the last index of the newArray
   newArray[j + 1] = '\0';

}

Any help with an explanation would be greatly appreciated.

Thank you,

Answer 1

#include <iostream>

void trimArray(const char *toTrim, char *newArray)
{
   //Initialization of the length variable to 0
   int length = 0;
   //Integer Index Variable (i)
   int i;
   //Integer Index Variable (j), initialized to 0
   int j = 0;

   //For loop gonig through the array toTrim to find the NULL character aka the length of the array
   for (i = 0; toTrim[i] != '\0'; i++)
   {
       //Incrementation of length + 1 each time a character other than the NULL character is found
       length++;
   }

   //For loop gonig through the array toTrim to find all of the characters that are not spaces
   //Starts at the last index of the array, and goes down by one each time
   //As long as i >= 0
   for (i = length - 1; i >= 0; i--)
   {
       //If condition setting all the non-space elements of the array equal to the values of another index
       //No space = character
       if (toTrim[i] != ' ')
       {
           //Set the current index to the j variable
           j = i;
           break;
       }
   }

   // count starting spaces, and do not include them
   int spaces = 0;

   //For loop going through the arrays newArray and toTrim at index i setting the values equal until j
   for (i = 0; i <= j; i++)
   {
    if(spaces == 0 && toTrim[i] == ' ') {
        spaces++;
    } else {
            newArray[i - spaces] = toTrim[i];
    }
       //All characters from the toTrim Array are put into the newArray
   }

   //Adding a NULL character to the last index of the newArray
   newArray[j + 1 - spaces] = '\0';

}

using namespace std;

int main() {
    char dest[100];
    trimArray(" hi ", dest);
    cout << "*" << dest << "*" << endl;
    trimArray(" hi", dest);
    cout << "*" << dest << "*" << endl;
    trimArray("hi ", dest);
    cout << "*" << dest << "*" << endl;
    trimArray(" ", dest);
    cout << "*" << dest << "*" << endl;
}




Hi. please find the answer above.. i have given comments so that it is very easy for you to understand the flow. In case of any doubts, please ask in comments. If the answer helps you, please upvote. Thanks!