CODEWITHSUNDEEP
c++file-ionewline
Nikhil Chilwant
Nikhil Chilwant

Reputation: 649

Detecting empty line from text file

I have text file like this:

7
a

bkjb
c


dea

hash_table is an array such that line no.-2=index of hash_table array that is every line corresponds to an element in array. The element may be empty line or character like "a\n" which will like this in text file:

a
//empty line

First number is used to decide the size an array hash_table. THe << operator is not treating empty line or '\n' char as string and hence not adding into array. I tried this but no use . Here is my try:

ifstream codes ("d:\\test3.txt"); //my text file

void create_table(int size, string hash_table[]) //creating array
{   string a;
    for(int i=0;i<size;i=i+1)
        {
        codes>>a;
        char c=codes.get();

        if(codes.peek()=='\n')
            {char b=codes.peek();
            a=a+string(1,b);
            }
        hash_table[i]=a;
        a.clear();
        }
}

void print(int size, string hash_table[])
{
    for(int i=0;i<size;i=i+1)
        {if(!hash_table[i].empty())
            {cout<<"hash_table["<<i<<"]="<<hash_table[i]<<endl;} 
        }
}

int main()
{
    int size;
    codes>>size;
    string hash_table[size];
    create_table(size, hash_table);
    print(size, hash_table);



}

NOTE: there can be any no. of empty lines with random sequence.

Upvotes: 0

Views: 4845

Answers (1)

jxh
jxh

Reputation: 70502

Use std::getline() instead of std::ifstream::operator >>(). The >> operator will skip over whitespace, including newlines.

std::string line;
while (std::getline(codes, line)) {
    //...do something with line
}

Upvotes: 2

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