Compilare: user.cpp: In function ‘int main()’: user.cpp:56:10: warning: unused variable ‘fin’ [-Wunused-variable] FILE*fin=freopen("bellmanford.in","r",stdin); ^ user.cpp:57:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&n,&m); ^ user.cpp:59:33: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d",&a,&b,&c); ^