Compilare: user.cpp: In function ‘long long int solve(unsigned int)’: user.cpp:50:13: warning: unused variable ‘x’ [-Wunused-variable] int x = c.size(); ^ user.cpp: In function ‘int main()’: user.cpp:20:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("secv5.in" , "r" , stdin); ^ user.cpp:21:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("secv5.out" , "w" , stdout); ^ user.cpp:23:43: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lld %lld %lld" , &n , &p , &u);// ^ user.cpp:28:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%ud" , &v[i]);// ^