【代码】求强连通分量的Kosaraju算法 

 1 program Xiong;
 2 var
 3         side:array[0..100,0..100] of boolean;
 4         p:array[0..100]of boolean;
 5         f:array[0..100]of longint;
 6         n,m,i,t,a,b,ans,time:longint;
 7 
 8 procedure dfs(m:longint);
 9 var
10         i:longint;
11 begin
12         p[m]:=true;
13         for i:=1 to n do
14             if (side[m,i])and(p[i]=false) then
15                 dfs(i);
16         inc(time);
17         f[time]:=m;
18 end;
19 
20 procedure dfs2(m:longint);
21 var
22         i:longint;
23 begin
24         p[m]:=false;
25         for i:=1 to n do
26             if side[i,m]and(p[i]) then
27                 dfs2(i);
28 end;
29 
30 begin
31         assign(input,'circle.in');reset(input);
32         assign(output,'circle.out');rewrite(output);
33 
34         readln(n,m);
35         for i:=1 to m do begin
36             read(a,b);
37             side[a,b]:=true;
38         end;
39 
40         for i:=1 to n do
41             if p[i]=false then dfs(i);
42 
43         for i:=n downto 1 do
44             if p[f[i]] then begin
45                 inc(ans);
46                 dfs2(f[i]);
47             end;
48         write(ans);
49 
50         close(input);
51         close(output);
52 end.
感觉这个算法比tarjan好些多了，虽然可能慢一些，但是在数据范围不是很大的时候还是很实惠的嘛
posted @ 2012-04-26 14:07  不二的笨笨  阅读(244)  评论(0)    收藏  举报