No. of words in given file = 12

#include <fstream.h> //This include file is required to support ifstream class

int countwords(char fname[]) {
Passing fname as character array that would contain user given filename. Returning int data type that would contain the count of words.

ifstream ipfile(fname,ios::in); //Opening the filestream in input mode for the filename passed as function argument.

int c=0; //This would contain the word count thus initialised to 0 in the beginning.

if(!ipfile) return -1;
This line checks for file presence or openability so that errors can be avoided later. return value is set as -1 as normal return value when word is found or not found will be 0 or greatet.

while(!ipfile.eof()) { //This loop runs until end of file is not reached.

char word[50]=””;  //This char array would store the word collected from the file, This assumes that no word is larger than 49 characters assuming c++ puts null character at the end. This is most practical for any English word.

ipfile>>word; //Using the property of >> file extraction operator we collect a word from the file as this operator is able to collect data till first space it finds.

if(strlen(word)>0) c++; //If some word is actually present then its string length would be more than 0 and then only variable c, the word count is increased.
}
ipfile.close();  //File is closed
return c;  //word count is returned. if there is no word in file 0 would be returned.
}

int main() {
int c=countwords(“NOTES.TXT”); //The filename is passed to the given function and then the wordcount will come in variable c.
if(c==-1) {cout<<“Unable to open file”<<endl; return 1;} //if -1 is returned then file was not possible to open.
cout<<“No. of words in given file = “<<c<<endl; //Word count is printed.
return 0;
}

Notes

• This code can be tested on your local system only once a file with given content is created with its name as NOTES.TXT
• It is always a good practice to check if the file has been opened properly. It will not open properly in many cases. One can reach the OS by returning an error to the operating system.
• For DOS testing with TurboC environment, learners are advised to keep the input file in the BIN directory are the turboc program runs from there.

Common Errors

• Programmers often increase word count without checking for string length of collected word. In that case extra word count will return.
• If we break the while loop by putting extra eof() check before counting, then a file containing single word  will give 0 word count. for e.g. if the while loop is written as follows.
  char word[50]=””;
  while(!ipfile.eof())
  {
  ipfile>>word;
  if(ipfile.eof()) break;
  c++;
  }