bzoj1098 1301

这两题很类似，都是在补图上搜索

但是由于补图太大我们不能建出来

考虑先从一个点搜，每次搜可以搜的点，

然后维护一个链表，记录当前还没有搜过的点，搜过之后从链表中删除即可

  1 type node=record
  2        po,next:longint;
  3      end;
  4
  5 var e:array[0..4000010] of node;
  6     l:array[0..100010] of node;
  7     p,q,ans:array[0..100010] of longint;
  8     can,v:array[0..100010] of boolean;
  9     s,i,n,m,len,x,y:longint;
 10
 11 procedure add(x,y:longint);
 12   begin
 13     inc(len);
 14     e[len].po:=y;
 15     e[len].next:=p[x];
 16     p[x]:=len;
 17   end;
 18
 19 procedure swap(var a,b:longint);
 20   var c:longint;
 21   begin
 22     c:=a;
 23     a:=b;
 24     b:=c;
 25   end;
 26
 27 procedure sort(l,r:longint);
 28   var i,j,x:longint;
 29   begin
 30     i:=l;
 31     j:=r;
 32     x:=ans[(l+r) shr 1];
 33     repeat
 34       while ans[i]<x do inc(i);
 35       while x<ans[j] do dec(j);
 36       if not(i>j) then
 37       begin
 38         swap(ans[i],ans[j]);
 39         inc(i);
 40         dec(j);
 41       end;
 42     until i>j;
 43     if l<j then sort(l,j);
 44     if i<r then sort(i,r);
 45   end;
 46
 47 procedure del(i:longint);
 48   begin
 49     l[l[i].po].next:=l[i].next;
 50     if l[i].next<>-1 then l[l[i].next].po:=l[i].po;
 51   end;
 52
 53 procedure bfs;
 54   var f,r,i,t:longint;
 55   begin
 56     while l[0].next<>-1 do
 57     begin
 58       f:=1;
 59       r:=1;
 60       v[l[0].next]:=true;
 61       q[1]:=l[0].next;
 62       del(l[0].next);
 63       t:=1;
 64       while f<=r do
 65       begin
 66         x:=q[f];
 67         i:=p[x];
 68         while i<>0 do
 69         begin
 70           can[e[i].po]:=true;
 71           i:=e[i].next;
 72         end;
 73         i:=l[0].next;
 74         while i>-1 do
 75         begin
 76           if not v[i] and not can[i] then
 77           begin
 78             inc(r);
 79             q[r]:=i;
 80             del(i);
 81             inc(t);
 82             v[i]:=true;
 83           end;
 84           i:=l[i].next;
 85         end;
 86         i:=p[x];
 87         while i<>0 do
 88         begin
 89           can[e[i].po]:=false;
 90           i:=e[i].next;
 91         end;
 92         inc(f);
 93       end;
 94       inc(s);
 95       ans[s]:=t;
 96     end;
 97   end;
 98
 99 begin
100   readln(n,m);
101   for i:=1 to m do
102   begin
103     readln(x,y);
104     add(x,y);
105     add(y,x);
106   end;
107   for i:=1 to n do
108   begin
109     l[i].po:=i-1;
110     l[i-1].next:=i;
111   end;
112   l[n].next:=-1;
113   bfs;
114   sort(1,s);
115   writeln(s);
116   for i:=1 to s do
117     write(ans[i],‘ ‘);
118   writeln;
119 end.

1098

 1 type node=record
 2        po,next:longint;
 3      end;
 4
 5 var e:array[0..2000010] of node;
 6     l:array[0..100010] of node;
 7     p:array[0..100010] of longint;
 8     can:array[0..100010] of boolean;
 9     i,n,m,x,y,len:longint;
10
11 procedure add(x,y:longint);
12   begin
13     inc(len);
14     e[len].po:=y;
15     e[len].next:=p[x];
16     p[x]:=len;
17   end;
18
19 procedure del(i:longint);
20   begin
21     l[l[i].po].next:=l[i].next;
22     if l[i].next<>-1 then l[l[i].next].po:=l[i].po;
23   end;
24
25 procedure dfs(x:longint);
26   var i,j:longint;
27   begin
28     writeln(x);
29     del(x);
30     i:=p[x];
31     while i<>0 do
32     begin
33       can[e[i].po]:=true;
34       i:=e[i].next;
35     end;
36     i:=l[0].next;
37     while i>-1 do
38     begin
39       if not can[i] then
40       begin
41         j:=p[x];
42         while j<>0 do
43         begin
44           can[e[j].po]:=false;
45           j:=e[j].next;
46         end;
47         dfs(i);
48         exit;
49       end;
50       i:=l[i].next;
51     end;
52   end;
53
54 begin
55   readln(n,m);
56   for i:=1 to m do
57   begin
58     readln(x,y);
59     add(x,y);
60     add(y,x);
61   end;
62   for i:=1 to n do
63   begin
64     l[i-1].next:=i;
65     l[i].po:=i-1;
66   end;
67   l[n].next:=-1;
68   dfs(1);
69 end.

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