Compilare: main.cpp: In function 'void euclid(int&, int&, int, int)': main.cpp:4:7: warning: unused variable 'next_gcd' [-Wunused-variable] int next_gcd, new_x, new_y; ^~~~~~~~ main.cpp: In function 'int main()': main.cpp:17:36: 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); ^ main.cpp:18:38: 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); ^ main.cpp:19:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ main.cpp:21:34: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d", &a, &b, &c); ^