题意

Solution

压位+前缀和

1 #include 
      
        2 #include 
       
         3 #include 
        
          4 #include 
         
           5 #define ll int 6 using namespace std; 7 const ll mod=100000007; 8 inline void read(ll &k) 9 {10     ll f=1;char c=getchar();k=0;11     while (c<'0'||c>'9')c=='-'&&(f=-1),c=getchar();12     while (c>='0'&&c<='9')k=k*10+c-'0',c=getchar();13     k*=f;14 }15 const int maxn=1000010;16 ll n,q,k,aa,bb,cc;17 ll last[maxn],next[maxn],tot,c[maxn],to[maxn],sum[maxn];long long cost[233];18 bool v[maxn];19 void dfs(ll now,ll fa)20 {21     v[now]=1;ll cur=last[now];22     while (cur)23     {24         if (!v[to[cur]])25         {26             sum[to[cur]]=sum[now]^(1<<(c[cur]-1));27             dfs(to[cur],now);28         }29         cur=next[cur];30     }    31 }32 int main()33 {34     freopen("mahou.in","r",stdin);35     freopen("mahou.out","w",stdout);36     read(n);read(q);read(k);37 //    printf("..............qaq%lld%lld%lld\n",n,q,k);38     for (int i=1;i