CODEWITHSUNDEEP
c++
user3309317
user3309317

Reputation: 11

"If" statement not returning correct information.

char capSentStart(char paragraph[], char newParagraph[])
{
    for(int i = 0; i < 301; ++i)
    {   
        if(paragraph[i] == '.' && paragraph[i + 1] == ' ')
        {   
            newParagraph[i] = '.';
            newParagraph[i + 1] = ' ';
            newParagraph[i + 2] = ' ';
            newParagraph[i + 3] = toupper(paragraph[i + 2]);
            ++i;
        }   
        else
        {   
            newParagraph[i] = paragraph[i];
        }   
    }   
}

If you input say the "paragraph" Dude. dude. dude. dude. and then cout << newParagraph; it prints the same paragraph with nothing changed.

Upvotes: 1

Views: 102

Answers (6)

macroland
macroland

Reputation: 1025

char capSentStart(char paragraph[], char newParagraph[])
{
    int index=0;

    for(int i = 0; i < 301; ++i)
    {  
        index=i; 
        if(paragraph[i] == '.' && paragraph[i + 1] == ' ')
        {   
            newParagraph[i] = '.';
            newParagraph[i + 1] = ' ';
            newParagraph[i + 2] = ' ';
            newParagraph[i + 3] = toupper(paragraph[i + 2]);
            index=i+3;
       }   
       else
       {   
           newParagraph[i] = paragraph[i];
       } 
       i=index;
    }   
}

Upvotes: 0

nitish712
nitish712

Reputation: 19764

As per your code, if the current character is ".", then you are doing what you want inside the if condition. Consider the cases, when the current character is not ".". You are merely copying the original paragraph which replaces the previous characters in the newParagraph.

Say input: Dude. dude.

When the current character is the first ., the newParagraph at the end of iteration is:

Dude. D___

where _ indicates the characters yet to be filled.

But, in the next four iterations, we don't find a .. So, you are copying the data from the input into the newParagraph thus over-writing the changes.

Dude. dude.

EDIT:

Your code is trying to convert the first character of every sentence to upper Case. Here is how it should be modified:

char capSentStart(char paragraph[], char newParagraph[])
{
    int new_paragraph_idx=0;
    for(int i = 0; i < 301; ++i)
    {   
        if(paragraph[i] == '.' && paragraph[i + 1] == ' ')
        {   
            newParagraph[new_paragraph_idx++] = '.';
            newParagraph[new_paragraph_idx++] = ' ';
            newParagraph[new_paragraph_idx++] = ' ';
            newParagraph[new_paragraph_idx++] = toupper(paragraph[i + 2]);
            ++i;
        }   
        else
        {   
            newParagraph[new_paragraph_idx++] = paragraph[i];
        }   
    }   
}

Put a new_ptr which actually fills the newParagraph separately, thus preventing the over-writing. And also take care of the bounds of the strings. Otherwise you might end up with a SIGSEGV

Upvotes: 2

dwschrute
dwschrute

Reputation: 104

Executing the first iteration in if(paragraph[i] == '.' && paragraph[i + 1] == ' '), gives:

          paragraph[i] = '.'
                    ^
   paragraph = "Dude. dude.  ..."
newParagraph = "Dude. D         "

After ++i and the increment of i in the forloop, i moves to the following:

            paragraph[i] = 'd'
                      ^
   paragraph = "Dude. dude.  ..."
newParagraph = "Dude. D         "

But this time, the iteration executes the code in else.

else
{
    newParagraph[i] = paragraph[i];
}

This changes the newParagraph[i] which is D to paragraph[i], which is d.

            paragraph[i] = 'd'
                      ^
   paragraph = "Dude. dude.  ..."
newParagraph = "Dude. d         "   //'D' is changed back to 'd'

Afterwards, newParagraph just get overwritten into paragraph.

Upvotes: 0

Dhananjay Athare
Dhananjay Athare

Reputation: 1

Use following:

char capSentStart(char paragraph[], char newParagraph[])
{

    for(int i = 0,j = 0; i < 301; ++i,++j)
    {   
        if(paragraph[i] == '.' && paragraph[i + 1] == ' ')
        {   
            newParagraph[j] = '.';
            newParagraph[j + 1] = ' ';
            newParagraph[j + 2] = ' ';
            newParagraph[j + 3] = toupper(paragraph[i + 2]);
            j=j+3;
            i=i+2;
        }   
        else
        {   
            newParagraph[j] = paragraph[i];
        }   
    }   
}

Upvotes: 0

elnigno
elnigno

Reputation: 1821

You are always writing based on the index i. Even if you write on higher indexes in newParagraph, then the follow iterations will overwrite what was done.

Upvotes: 0

mrks
mrks

Reputation: 1441

In the True case of the if statement you are filling newParagraph but when you keep itterating you are overwriting them again in the false case of the if statement. You should have two itterating variables for Paragraph and new Paragraph.

In order to give you a more detailed answer you should tell us the expeced output.

Upvotes: 0

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