Compilare: user.cpp: In function ‘int main()’: user.cpp:156:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0; i < P.size(); i++) { ^ user.cpp:157:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (j = i + 1; j < P.size(); j++) { ^ user.cpp:118:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("cerc.in","r",stdin); ^ user.cpp:119:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("cerc.out","w",stdout); ^ user.cpp:121:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:123:58: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lf%lf%lf", &C[i].O.x, &C[i].O.y, &C[i].R); ^