Compilare: user.cpp: In function ‘int main()’: user.cpp:13:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(n <= b){ ^ user.cpp:16:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(n <= b){ ^ user.cpp:19:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(n <= b){ ^ user.cpp:22:41: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(n >= a && n <= b){ ^ user.cpp:22:51: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(n >= a && n <= b){ ^ user.cpp:26:50: warning: unused variable ‘nr2’ [-Wunused-variable] int nr4 = 0, nr2 = 0, r2 = 0; ^ user.cpp:35:45: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] else if(n > b) break; ^ user.cpp:8:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("smooth.in", "r", stdin); ^ user.cpp:9:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("smooth.out", "w", stdout); ^ user.cpp:10:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lld%lld", &a, &b); ^