int sum[10000001],scc[10000001],d[10000001],ans,in[1000001],out[10000001],hc[10000001],vc[10000001],nc[10000001],cnt,tmp,ins[10000001],dfn[10000001],low[1000001],n,m ...
int hc[10000001],vc[10000001],nc[10000001],cnt,tmp,ins[10000001],dfn[10000001],low[1000001],n,m,cv,cu,head[10000001],ver[10000001],nex[10000001],c[10000001]; ...