Compilare: user.cpp: In function ‘void insert(long int)’: user.cpp:17: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘long int verif(long int)’: user.cpp:27: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘long int dif(long int)’: user.cpp:40: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘int main()’: user.cpp:67: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp:68: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp:70: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result