Compilare: user.cpp: In function ‘void DFS(int)’: user.cpp:38:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<v[x].size();i++) ^ user.cpp: In function ‘void Update(int, int, int)’: user.cpp:43:11: warning: unused variable ‘tx’ [-Wunused-variable] { int i,tx,aux=y,nr=0,cmx=-inf,n1,n2; ^ user.cpp:63:56: warning: ‘n2’ may be used uninitialized in this function [-Wmaybe-uninitialized] if (cost<cmx) {res-=cmx-cost; c[n1][n2]=c[n2][n1]=0; c[x][y]=c[y][x]=cost;} ^ user.cpp:63:56: warning: ‘n1’ may be used uninitialized in this function [-Wmaybe-uninitialized]