ZJOI2007矩阵游戏

 1 var i,j,n,t:longint;
 2     flag:boolean;
 3     p:array[0..250] of longint;
 4     v:array[0..250] of boolean;
 5     a:array[0..250,0..250] of longint;
 6 function find(x:longint):boolean;
 7  var i:longint;
 8  begin
 9   for i:=1 to n do
10    if (not(v[i])) and (a[x,i]=1) then
11      begin
12        v[i]:=true;
13        if (p[i]=0) or (find(p[i])) then
14          begin
15            p[i]:=x;
16            exit(true);
17          end;
18      end;
19   exit(false);
20  end;
21 procedure init;
22  begin
23    readln(n);
24    fillchar(p,sizeof(p),0);
25    for i:=1 to n do
26     begin
27       for j:=1 to n do read(a[i,j]);
28       readln;
29     end;
30  end;
31 procedure main;
32  begin
33    flag:=true;
34    for i:=1 to n do
35     begin
36       fillchar(v,sizeof(v),false);
37       if not(find(i)) then begin flag:=false;break;end;
38     end;
39    if flag then writeln(‘Yes‘) else writeln(‘No‘);
40  end;
41 
42 begin
43   readln(t);
44   while t>0 do
45    begin
46      dec(t);
47      init;
48      main;
49    end;
50 end.