Compilare: user.cpp: In function ‘int find(int, int)’: user.cpp:22: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘void add(int, int)’: user.cpp:32: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘int erase(int, int)’: user.cpp:41: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘void read(char*)’: user.cpp:53: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result user.cpp: In function ‘int main()’: user.cpp:76: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:77: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result /tmp/ccEEtLaE.o: In function `main': user.cpp:(.text+0x15e): warning: the `gets' function is dangerous and should not be used.