work/source: In function ‘int main()’:
work/source:100: error: ‘stdin’ was not declared in this scope
work/source:100: error: ‘freopen’ was not declared in this scope
work/source:101: error: ‘stdout’ was not declared in this scope
work/source:103: error: ‘scanf’ was not declared in this scope
work/source:124: error: ‘printf’ was not declared in this scope
work/source:126: error: ‘fclose’ was not declared in this scope
