Compilare: user.cpp: In function ‘int main()’: user.cpp:49: warning: suggest parentheses around ‘-’ inside ‘<<’ user.cpp:50: warning: suggest parentheses around ‘-’ inside ‘<<’ user.cpp:53: warning: suggest parentheses around ‘+’ inside ‘>>’ user.cpp:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:40: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:42: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result