Compilare: user.cpp: In function ‘int main()’: user.cpp:50:52: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (register int j = 0; j < lines[i].size(); ++j) ^ user.cpp:25:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("cerc3.in", "r", stdin); ^ user.cpp:26:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("cerc3.out", "w", stdout); ^ user.cpp:27:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] int n; scanf("%d", &n); ^ user.cpp:30:57: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] double x, y, r; scanf("%lf %lf %lf", &x, &y, &r); ^