Borderou de evaluare (job #12814)

Compilare: user.cpp: In function ‘int main()’: user.cpp:6:13: warning: unused variable ‘a’ [-Wunused-variable] user.cpp:6:15: warning: unused variable ‘b’ [-Wunused-variable] user.cpp:6:23: warning: unused variable ‘j’ [-Wunused-variable] user.cpp:7:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] user.cpp:8:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result]