Compilare: user.cpp: In function ‘int main()’: user.cpp:10: warning: comparison between signed and unsigned integer expressions user.cpp:22: warning: format ‘%ld’ expects type ‘long int’, but argument 3 has type ‘int’ user.cpp:7: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:8: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:9: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result /tmp/cc00h5SS.o: In function `main': user.cpp:(.text+0x58): warning: the `gets' function is dangerous and should not be used.