Compilare: user.c: In function ‘main’: user.c:18:11: warning: suggest explicit braces to avoid ambiguous ‘else’ [-Wparentheses] if(!v[g[j][i]]) ^ user.c:5:9: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("bellmanford.in","r",stdin),freopen("bellmanford.out","w",stdout),scanf("%d%d",&n,&m); ^ user.c:5:45: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("bellmanford.in","r",stdin),freopen("bellmanford.out","w",stdout),scanf("%d%d",&n,&m); ^ user.c:5:81: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] freopen("bellmanford.in","r",stdin),freopen("bellmanford.out","w",stdout),scanf("%d%d",&n,&m); ^ user.c:9:12: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d",&a[i],&b[i],&c[i]),w[a[i]]++; ^