C++ Data files

[Ec4U2du]

how can i open a file from a program and count the lines in the files and return the total amount of lines in the file to the program?

[Fordy]

Maybe not the most efficient method, but probably the easiest for text files

#include <fstream>
#include <iostream>
#include <string>




int main(){

	std::ifstream in;
	
	std::string filename;
	
	std::cout << "Enter name of file" << std::endl;
	
	std::getline(std::cin,filename);//get name of file
	
	in.open(filename.c_str());//open it
	
	if(!in.is_open()){//see if open was successful
		std::cout << "Could not open " << filename;
		return 1;
	}
	
	std::string dummy;//dummy string to hold read info
	int n = 0;//line count
	
	dummy.reserve(500);//try reserve memory (not needed, but may help)
	
	while(!in.eof()){//while not at end of file
		std::getline(in,dummy);//read a line into a string
		++n;//increase count	
	}
		
	std::cout << "Total line count = " << n;

}

[ammar]

I think you have to count how many times the '\n' appeared in the text file.