Compilare: user.cpp: In function ‘int main()’: user.cpp:11:9: warning: unused variable ‘n’ [-Wunused-variable] int n, i, R, P; ^ user.cpp:13:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("dstar.in","r", stdin); ^ user.cpp:15:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &R, &P); ^ user.cpp:16:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lf", &ant); ^ user.cpp:19:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lf", &u); ^ user.cpp:21:17: warning: ‘sum’ may be used uninitialized in this function [-Wmaybe-uninitialized] sum += u; ^