Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:33:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0; i<graph[element].size() && !found; i++) ^ user.cpp: In function ‘int main()’: user.cpp:66:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i = 0; i < visited.size() && i < n; i++) ^ user.cpp:54:15: warning: unused variable ‘c’ [-Wunused-variable] int i,x,y,c=0; ^