Compilare: main.cpp: In function 'void euler(int)': main.cpp:12:5: warning: unused variable 'i' [-Wunused-variable] int i; ^ main.cpp: In function 'int main()': main.cpp:37:39: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("ciclueuler.in","r",stdin); ^ main.cpp:38:41: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("ciclueuler.out","w",stdout); ^ main.cpp:39:25: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&n,&m); ^ main.cpp:41:29: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&x,&y); ^