Compilare: user.cpp: In function ‘int main()’: user.cpp:20:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("euclid3.in", "r", stdin); ^ user.cpp:21:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("euclid3.out", "w", stdout); ^ user.cpp:24:18: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &t); ^ user.cpp:27:32: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d", &a, &b, &c); ^ user.cpp:11:12: warning: ‘x’ may be used uninitialized in this function [-Wmaybe-uninitialized] int x0 = x; ^ user.cpp:28:9: note: ‘x’ was declared here int x, y; ^ user.cpp:12:12: warning: ‘y’ may be used uninitialized in this function [-Wmaybe-uninitialized] int y0 = y; ^ user.cpp:28:12: note: ‘y’ was declared here int x, y; ^