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c++iofstream

Reading and storing integers in a file

I have a file.txt such as : 

15 25 32 // exactly 3 integers in the first line. 
string1
string2
string3
*
*
*
*

What I want to do is, reading 15,25,32 and store them into lets say int a,b,c;

Is there anyone to help me ? Thanks in advance.

Solution

  • You can use a std::ifstream to read file content:

    #include <fstream>
std::ifstream infile("filename.txt");

    Then you can read the line with the numbers using std::getline():

    #include <sstream>
#include <string>
std::string line;
std::getline(infile, line);

    Then, you can use a std::istringstream to parse the integers stored in that line:

    std::istringstream iss(line);
int a;
int b;
int c;

iss >> a >> b >> c;