Compilare: user.cpp: In function ‘int main()’: user.cpp:74:9: warning: unused variable ‘i’ [-Wunused-variable] int i, l; ^ user.cpp:71:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("expresie3.in", "r", stdin); ^ user.cpp:72:42: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("expresie3.out", "w", stdout); ^