bzoj3140

首先考虑二维的情况

min(x,y)也就意味着确定最小后，另外一维肯定打满

然后最小那个如果是k的话就相当于用k*1次——这不就是行列覆盖吗，二分图秒之

三维呢？考虑到a*b*c<=5000也就是最小的那维不超过17

那么我们直接穷举那维用哪些，然后另外的就跟二维一样了

注意要优化常数

 type node=record
        po,next:longint;
      end;

 var e:array[..] of node;
     d:array[..,..] of longint;
     p,cx,cy:array[..] of longint;
     v:array[..] of boolean;
     can,f:array[..] of boolean;
     x,tt,j,k,len,ans,i,t,a,b,c,a0,b0,c0:longint;

 function max(a,b:longint):longint;
   begin
     if a>b then exit(a) else exit(b);
   end;

 procedure add(x,y:longint);
   begin
     inc(len);
     e[len].po:=y;
     e[len].next:=p[x];
     p[x]:=len;
   end;

 procedure swap(var a,b:longint);
   var c:longint;
   begin
     c:=a;
     a:=b;
     b:=c;
   end;

 function dfs(x:longint):longint;
   var i,y:longint;
   begin
     i:=p[x];
     while i<> do
     begin
       y:=e[i].po;
       if not v[y] then
       begin
         v[y]:=true;
         if (cy[y]=-) or (dfs(cy[y])=) then
         begin
           cy[y]:=x;
           cx[x]:=y;
           exit();
         end;
       end;
       i:=e[i].next;
     end;
     exit();
   end;

 function cal(s:longint):longint;
   var i,j:longint;
   begin
     cal:=s;
     len:=;
     for i:= to b do
     begin
       p[i]:=;
       cx[i]:=-;
     end;
     for i:= to c do
       cy[i]:=-;
     for i:= to t do
       if not f[d[i,a0]] then
         add(d[i,b0],d[i,c0]);
     for i:= to b do
       if cx[i]=- then
       begin
         for j:= to c do
           v[j]:=false;
         cal:=cal+dfs(i);
         if cal>=ans then exit;
       end;
   end;

 procedure work(x,s:longint);
   var m:longint;
   begin
     if s>=ans then exit;
     if x=a+ then
     begin
       m:=cal(s);
       if m<ans then ans:=m;
     end
     else begin
       f[x]:=false;
       work(x+,s);
       if can[x] then
       begin
         f[x]:=true;
         work(x+,s+);
         f[x]:=false;
       end;
     end;
   end;

 begin
   readln(tt);
   while tt> do
   begin
     dec(tt);
     readln(a,b,c);
     a0:=; b0:=; c0:=;
     t:=;
     for i:= to a do
       for j:= to b do
         for k:= to c do
         begin
           read(x);
           if x= then
           begin
             inc(t);
             d[t,]:=i;
             d[t,]:=j;
             d[t,]:=k;
           end;
         end;
     if (b<=a) and (b<=c) then
     begin
       swap(a0,b0);
       swap(a,b);
     end
     else if (c<=a) and (c<=b) then
     begin
       swap(a0,c0);
       swap(a,c);
     end;
     if b>c then
     begin
       swap(b0,c0);
       swap(b,c);
     end;
     fillchar(can,sizeof(can),false);
     for i:= to t do
       can[d[i,a0]]:=true;
     ans:=;
     for i:= to a do
       if can[i] then inc(ans);
     fillchar(f,sizeof(f),false);
     work(,);
     writeln(ans);
   end;
 end.