Compilare: user.cpp: In function ‘int main()’: user.cpp:100:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("rubarba.in", "r", stdin); ^ user.cpp:101:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("rubarba.out", "w", stdout); ^ user.cpp:103:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%i", &N); ^ user.cpp:105:50: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%i %i", &V[i].first, &V[i].second); ^ user.cpp: In function ‘void RotatingCalipers()’: user.cpp:66:22: warning: ‘l’ may be used uninitialized in this function [-Wmaybe-uninitialized] int i, j = 1, k, l; ^