Compilare: main.cpp: In function 'int main()': main.cpp:24:45: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen ( "matrice5.in" , "r" , stdin ) ; ^ main.cpp:25:47: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen ( "matrice5.out" , "w" , stdout ) ; ^ main.cpp:29:26: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf ( "%d" , & t ) ; ^ main.cpp:33:54: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf ( "%d%d%d%d" , & n , & m , & p , & k ) ; ^