lacuri.cpp: In function 'int main()': lacuri.cpp:23: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result lacuri.cpp:24: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result lacuri.cpp:25: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result lacuri.cpp:36: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result lacuri.cpp:22: warning: 'nr' may be used uninitialized in this function