Compilare: user.cpp: In function ‘void add(int, int)’: user.cpp:59:9: warning: unused variable ‘l’ [-Wunused-variable] int l = 0, r = ans; ^ user.cpp:59:16: warning: unused variable ‘r’ [-Wunused-variable] int l = 0, r = ans; ^ user.cpp: In function ‘int main()’: user.cpp:85:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &m); ^ user.cpp:89:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &x); ^ user.cpp:95:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &x); ^