yo2那边上不去。。。就来这先写吧。此题为标准的bfs。但是dfs，枚举也能过。我简单的go了一下就过了。。。。就是这个效率。。。。不知我这个搜索叫什么，深度没有下限，搜不到答案就一直往下搜，直到搜到答案为止。哈哈，今天改程序风格了。。。
TASK: clocks
LANG: PASCAL
Compiling...
Compile: OK
Executing...
Test 1: TEST OK [0.036 secs]
Test 2: TEST OK [0.008 secs]
Test 3: TEST OK [0.432 secs]
Test 4: TEST OK [0.644 secs]
Test 5: TEST OK [0.528 secs]
Test 6: TEST OK [0.756 secs]
Test 7: TEST OK [0.848 secs]
Test 8: TEST OK [0.856 secs]
Test 9: TEST OK [0.86 secs]
All tests OK.
请看程序。。。
--------------------------------------------------------华丽的分割线------------------------------------------------------
{
ID:parachutes
PROG:clocks
LANG:PASCAL
}
const method:array[1..9] of string=
('ABDE','ABC','BCEF','ADG','BDEFH','CFI','DEGH','GHI','EFHI');//变换规则。
type tclock=array[1..9] of longint;//记录9个clock
tans=array[1..100] of longint;//记录答案。
var q,a:tans;
used,clock:tclock;
maxdep:longint;//最大深度
procedure init;//初始化，读入。
var i:longint;
begin
assign(input,'clocks.in'); reset(input);
for i:=1 to 9 do begin
read(clock[i]);
clock[i]:=(clock[i] div 3) and 3;
end;
maxdep:=maxlongint;
close(input);
end;
function check(c:Tclock):boolean;//判断是否全部12点
var i:longint;
begin
for i:=1 to 9 do
if c[i]<>0 then exit(false);
exit(true);
end;
procedure go(dep,last:longint;st:Tclock);//深搜过程。。。
var i,j,k:longint;
ss:Tclock;
begin
if dep>maxdep then exit;
if check(st) and (dep<maxdep) then//找到答案则输出
begin
maxdep:=dep;
a:=q;
exit;
end;
for i:=last to 9 do
if used[i]<4 then begin//可以叫剪枝吧。。。变换4次及以上和没变一样。。
inc(used[i]);
q[dep]:=i;
ss:=st;
for j:=1 to length(method[i]) do begin
k:=ord(method[i][j])-64;
ss[k]:=(ss[k]+1) and 3;
end;
go(dep+1,i,ss);
dec(used[i]);
end;
end;
procedure print;//答案输出
var i:longint;
begin
assign(output,'clocks.out'); rewrite(output);
dec(maxdep);
for i:=1 to maxdep do
if i<>maxdep then write(a[i],' ') else
writeln(a[i]);
close(output);
end;
begin
init;
go(1,1,clock);
print;
end.
