Compilare: main.cpp: In function 'int main()': main.cpp:11:46: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen ( "diagonale.in" , "r" , stdin ) ; ^ main.cpp:12:48: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen ( "diagonale.out" , "w" , stdout ) ; ^ main.cpp:16:26: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf ( "%d" , & n ) ; ^ main.cpp:21:34: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf ( "%d" , & x ) ; ^