Compilare: user.cpp: In function ‘int main()’: user.cpp:87:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen( "sub.in" , "r", stdin ); ^ user.cpp:88:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen( "sub.out", "w", stdout ); ^ user.cpp:90:22: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf( "%d", &N ); ^ user.cpp:92:32: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf( "%s", A[i] + 1 ); ^ user.cpp:99:22: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf( "%d", &M ); ^ user.cpp:101:32: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf( "%s", B[i] + 1 ); ^