pod.cpp: In function 'int main()': pod.cpp:44: warning: unused variable 'dis' pod.cpp:42: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result pod.cpp:43: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result pod.cpp:45: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result pod.cpp:46: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result pod.cpp:49: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result