Why is g++ Giving Me Conflicting Errors While Compiling? [closed] - c++

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I am attempting to compile my second, (still noobish) C++ program, and g++ is giving me these errors:
new.cpp: In function ‘int main()’:
new.cpp:10:4: error: ‘cin’ was not declared in this scope
cin >> name;
is the first. Here's the second:
^~~
new.cpp:10:4: note: suggested alternative:
In file included from new.cpp:1:
/usr/include/c++/8/iostream:60:18: note: ‘std::cin’
extern istream cin; /// Linked to standard input
^~~
and I believe these are telling me to change both ways to write it to the other. I have tried changing both, and I'm not sure how to fix this. Here is the program:
#include <iostream>
#include <string>
int main() {
std::string age;
std::string name;
std::cout << "Please input your age.";
std::cin >> age;
std::cout << "Please input your name.";
cin >> name;
return 0;
}
(CLOSED)

Answer 1

Here is a little bit of explanation for a c++ and g++ newbie:
new.cpp:10:4: error: ‘cin’ was not declared in this scope
cin is declared under the std namespace. See https://en.cppreference.com/w/cpp/io/cin
The second one is not an error, but a suggestion by the compiler by pointing to the alternative found by the compiler. It gives a hint about std::cin.
note: suggested alternative:
In file included from new.cpp:1:
/usr/include/c++/8/iostream:60:18: note: ‘std::cin’
extern istream cin; /// Linked to standard input
^~~
At line 10, you are using cin from the global namespace. Therefore, the compiler complains that it can't find the declaration of cin.
Our fellow already provided a fix for you by changing line 10 to: std::cin >> name;.
#include <iostream>
#include <string>
int main() {
std::string age;
std::string name;
std::cout << "Please input your age.";
std::cin >> age;
std::cout << "Please input your name.";
std::cin >> name;
return 0;
}