Compilare: user.cpp: In function ‘int main()’: user.cpp:3:300: warning: operation on ‘i’ may be undefined [-Wsequence-point] using namespace std;int x,m,n,y,d[50001],i;vector<int>a[50001];bool w[50001];vector<int>v;void D(int x){w[x]=1;for(int i=0;i<d[x];++i){int y=a[x][i];if(!w[y])D(y);}v.push_back(x);++m;}int main(){ifstream f("sortaret.in");f>>n>>m;for(;m--;)f>>x>>y,a[x].push_back(y);++m;i=n;for(;i;)d[i]=a[i--].size();for(i=1;i<=n;++i)if(!w[i])D(i);ofstream g("sortaret.out");for(;m;)g<<v[--m]<<" ";return 0;} ^