Compilare: user.cpp: In function ‘void input()’: user.cpp:29:36: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ( "%d%d%d" , &n , &k , &w ) ; ^ user.cpp: In function ‘int main()’: user.cpp:54:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ( "nmult.in" , "r" , stdin ) ; ^ user.cpp:55:41: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ( "nmult.out" , "w" , stdout ) ; ^