Compilare: main.cpp: In function 'int main()': main.cpp:13:46: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen ( "nrsubsecv.in" , "r" , stdin ) ; ^ main.cpp:14:48: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen ( "nrsubsecv.out" , "w" , stdout ) ; ^ main.cpp:18:34: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf ( "%d%d" , & n , & m ) ; ^ main.cpp:21:36: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf ( "%d" , & v [ i ] ) ; ^ main.cpp:48:38: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf ( "%d%d" , & x , & y ) ; ^