Compilare: user.cpp: In function ‘int main()’: user.cpp:70: warning: comparison between signed and unsigned integer expressions user.cpp:71: warning: comparison between signed and unsigned integer expressions user.cpp:93: warning: comparison between signed and unsigned integer expressions user.cpp:94: warning: comparison between signed and unsigned integer expressions user.cpp:24: warning: unused variable ‘xx’ user.cpp:20: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp:23: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp:57: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result