Compilare: user.cpp: In function ‘int main()’: user.cpp:117: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:118: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:123: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result user.cpp: In function ‘int find(node*, int)’: user.cpp:75: warning: control reaches end of non-void function /tmp/cc5oDwTw.o: In function `main': user.cpp:(.text+0x15c): warning: the `gets' function is dangerous and should not be used.