Log Message Timestamp

#include <iostream>
#include <string>
using namespace std;
void logMessage(string msg, bool var=false){
    if(!var){
        cout<<msg;
    }
    else{
        cout<<"[123456]"<<" "<<msg;
    }
}

int main() {
    int mode;
    string msg;
    cin >> mode >> msg;

    if (mode == 0) {
        logMessage(msg);            // use default argument
    } else {
        logMessage(msg, true);      // enable timestamp
    }

    return 0;
}