Compilare: main.cpp: In function 'int main()': main.cpp:26:19: warning: suggest explicit braces to avoid ambiguous 'else' [-Wparentheses] if(!v[p->x]) ^ main.cpp:12:98: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("bellmanford.in","r",stdin),freopen("bellmanford.out","w",stdout),scanf("%d%d",&n,&m); ^ main.cpp:12:98: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] main.cpp:12:98: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] main.cpp:15:33: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d",&k,&l,&r); ^