ai.cpp: In function 'int main()': ai.cpp:223: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result ai.cpp:224: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result ai.cpp:226: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result ai.cpp:229: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result ai.cpp: In function 'void marc1(int, int)': ai.cpp:39: warning: 'dl' may be used uninitialized in this function ai.cpp:39: warning: 'dc' may be used uninitialized in this function ai.cpp: In function 'void marc2(int, int)': ai.cpp:131: warning: 'dl' may be used uninitialized in this function ai.cpp:131: warning: 'dc' may be used uninitialized in this function