Compilare: main.cpp: In function 'int main()': main.cpp:6:39: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] #define files(FILENAME) read(FILENAME); write(FILENAME) ^ main.cpp:18:9: note: in expansion of macro 'files' files(FILENAME); ^~~~~ main.cpp:18:24: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] files(FILENAME); ^ main.cpp:20:23: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^ main.cpp:24:31: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&x); ^