Compilare: user.cpp: In function ‘int main()’: user.cpp:71: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp:77: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘node* insert(node*, int, int, node*, int)’: user.cpp:42: warning: control reaches end of non-void function user.cpp: In function ‘int main()’: user.cpp:63: warning: ‘start’ may be used uninitialized in this function