work/source: In function ‘int main()’:
work/source:12: error: ‘stdin’ was not declared in this scope
work/source:12: error: ‘freopen’ was not declared in this scope
work/source:13: error: ‘stdout’ was not declared in this scope
work/source:15: error: ‘scanf’ was not declared in this scope
work/source:28: error: ‘printf’ was not declared in this scope
