Borderou de evaluare (job #13842)

Compilare: user.cpp: In function 'int main()': user.cpp:8:23: warning: variable 'cn2' set but not used [-Wunused-but-set-variable] user.cpp:8:38: warning: variable 'cn3' set but not used [-Wunused-but-set-variable] user.cpp:8:42: warning: variable 'cn4' set but not used [-Wunused-but-set-variable] user.cpp:8:46: warning: unused variable 'b' [-Wunused-variable] user.cpp:6:39: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] user.cpp:7:40: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]