Compilare: user.cpp: In function ‘int main()’: user.cpp:49: warning: format ‘%ld’ expects type ‘long int’, but argument 4 has type ‘int’ user.cpp:17: warning: unused variable ‘A’ user.cpp:84: warning: unused variable ‘start2’ user.cpp:105: warning: unused variable ‘na’ user.cpp:13: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:14: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result