Roller Coaster in c++

roller_coaster.cpp

#include <iostream>
#include <fstream> // For ifstream
#include <string>
#include <locale> 
using namespace std;

int main(int argc, char* argv[]) {
    ifstream file;
    string line;
    file.open(argv[1]);
    std::locale loc;
    while (!file.eof()) 
    {   
        getline(file, line);
        bool capFlag = true;
        for (string::const_iterator it = line.begin(); it != line.end(); ++it) {            if (std::isalpha(*it,loc)) {
                if  (capFlag == true) {
                    cout << toupper(*it,loc);
                    capFlag = false;
                } else {
                    cout << tolower(*it,loc);
                    capFlag = true;
                }
            } else {
                cout << *it;
            }
        }
        cout << endl;
    }
}