【ZJOI2017 Round1练习&BZOJ5354】D7T3 room（DP）

题意：

思路：

写了两种版本

考场版本

 var dp:array[..,..]of longint;
     t:array[..,..]of longint;
     n,m,i,j,k,oo,ans,d1:longint;

 function min(x,y:int64):int64;
 begin
  if x<y then exit(x);
  exit(y);
 end;

 begin
  assign(input,'room.in'); reset(input);
  assign(output,'room.out'); rewrite(output);
  readln(n,m,d1);
  oo:=maxlongint>>;
  for i:= to n do
   for j:= to m do read(t[i,j]);

  for i:= to n do
  begin
   for j:= to m do
    for k:= to m do
     if j<>k then dp[j,k]:=dp[j,k]+t[i-,j]+t[i-,k]
      else dp[j,k]:=oo;

   for j:= to m do
    for k:= to m do dp[j,k]:=min(dp[j,k],dp[j-,k]+d1);

   for j:=m- downto  do
    for k:= to m do dp[j,k]:=min(dp[j,k],dp[j+,k]+d1);

   for j:= to m do
    for k:= to m do dp[j,k]:=min(dp[j,k],dp[j,k-]+d1);

   for j:= to m do
    for k:=m- downto  do dp[j,k]:=min(dp[j,k],dp[j,k+]+d1);
  end;
  ans:=oo;
  for i:= to m do
   for j:= to m do
    if i<>j then ans:=min(ans,dp[i,j]+t[n,i]+t[n,j]);
  writeln(ans);
  {for i:=1 to n do
   for j:=1 to m do
    for k:=1 to m do writeln(i,' ',j,' ',k,' ',dp[i,j,k]+t[i,j]+t[i,k]);}
  close(input);
  close(output);
 end.

赛后自测版本

 var dp:array[..,..,..]of longint;
     t:array[..,..]of longint;
     n,m,d1,i,j,k,ans:longint;

 function min(x,y:longint):longint;
 begin
  if x<y then exit(x);
  exit(y);
 end;

 begin
  assign(input,'room.in'); reset(input);
  assign(output,'room.out'); rewrite(output);
  readln(n,m,d1);

  for i:= to n do
   for j:= to m do read(t[i,j]);

  for i:= to n do
  begin
   for j:= to m do
    for k:= to m do
     if j<>k then dp[i,j,k]:=dp[i-,j,k]+t[i,j]+t[i,k]
      else dp[i,j,k]:=maxlongint>>;

   for j:= to m do
    for k:= to m do
     if (j<>k)and(j-<>k) then dp[i,j,k]:=min(dp[i,j,k],dp[i,j-,k]+d1);

   for j:=m- downto  do
    for k:= to m do
     if (j<>k)and(j+<>k) then dp[i,j,k]:=min(dp[i,j,k],dp[i,j+,k]+d1);

   for j:= to m do
    for k:= to m do
     if (j<>k)and(k-<>j) then dp[i,j,k]:=min(dp[i,j,k],dp[i,j,k-]+d1);

   for j:= to m do
    for k:=m- downto  do
     if (j<>k)and(k+<>j) then dp[i,j,k]:=min(dp[i,j,k],dp[i,j,k+]+d1);
  end;

  ans:=maxlongint;
  for i:= to m do
   for j:= to m do
    if i<>j then ans:=min(ans,dp[n,i,j]);
  writeln(ans);

  close(input);
  close(output);
 end.