P3469-[POI2008]BLO-Blockade 

 1 #include <bits/stdc++.h>
 2 #define _for(i,a,b) for(int i = (a);i < b;i ++)
 3 #define _rep(i,a,b) for(int i = (a);i > b;i --)
 4 #define INF 0x3f3f3f3f
 5 #define pb push_back
 6 #define maxn (500000+39)
 7 
 8 typedef long long ll;
 9 using namespace std;
10 inline ll read()
11 {
12     ll ans = 0;
13     char ch = getchar(), last = ' ';
14     while(!isdigit(ch)) last = ch, ch = getchar();
15     while(isdigit(ch)) ans = (ans << 1) + (ans << 3) + ch - '0', ch = getchar();
16     if(last == '-') ans = -ans;
17     return ans;
18 }
19 inline void write(ll x)
20 {
21     if(x < 0) x = -x, putchar('-');
22     if(x >= 10) write(x / 10);
23     putchar(x % 10 + '0');
24 }
25 int N,M;
26 int tot = 1;
27 int num = 0;
28 int head[maxn],ver[maxn*2],Next[maxn*2];
29 int dfn[maxn],low[maxn],Size[maxn];
30 ll ans[maxn];
31 bool cut[maxn];
32 void add(int x,int y)
33 {
34     ver[++tot] = y;
35     Next[tot] = head[x];
36     head[x] = tot;
37 }
38 void tarjan(int x)
39 {
40     dfn[x] = low[x] = ++num;
41     Size[x] = 1;
42     int flag = 0,sum = 0;
43     for(int i = head[x]; i; i = Next[i])
44     {
45         int y = ver[i];
46         if(!dfn[y])
47         {
48             tarjan(y);
49             Size[x] += Size[y];
50             low[x] = min(low[x],low[y]);
51             if(low[y] >= dfn[x])
52             {
53                 flag ++;
54                 ans[x] += (ll)Size[y]*(N-Size[y]);
55                 sum += Size[y];
56                 if(x != 1 || flag > 1)
57                     cut[x] = true;
58             }
59         }
60         else
61             low[x] = min(low[x],dfn[y]);
62     }
63     if(cut[x])
64         ans[x] += (ll)(N-sum-1)*(sum+1)+(N-1);
65     else
66         ans[x] = 2*(N-1);
67 }
68 int main()
69 {
70     N = read(),M = read();
71     _for(i,1,M+1)
72     {
73         int x = read();
74         int y = read();
75         if(x==y)
76             continue;
77         add(x,y);
78         add(y,x);
79     }
80     tarjan(1);
81     _for(i,1,N+1)
82     write(ans[i]),putchar('\n');
83     return 0;
84 }

 

posted @ 2019-09-29 09:31  Asurudo  阅读(151)  评论(0)    收藏  举报