minuni.cpp: In function 'void read_and_solve()': minuni.cpp:65: warning: unused variable 'j' minuni.cpp:65: warning: unused variable 'k' minuni.cpp:67: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result minuni.cpp:71: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result minuni.cpp: In function 'int main()': minuni.cpp:92: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result minuni.cpp:93: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result