supertri.cpp: In function 'int main()': supertri.cpp:89: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result supertri.cpp:90: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result supertri.cpp:96: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result supertri.cpp:99: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result supertri.cpp:92: warning: 'vb' may be used uninitialized in this function supertri.cpp:92: warning: 'vc' may be used uninitialized in this function supertri.cpp:92: warning: 'va' may be used uninitialized in this function