「Clover」杯NOIP模拟赛 III

编年史

  打个表然后暴力就行，也可以蔡勒公式。

const first:array[1582..2012] of shortint=
(5,6,0,2,3,4,5,0,1,2,3,5,6,0,1,3,4,5,6,1,2,3,4,6,0,1,2,4,5,6,0,2,3,4,5,0,1,2,3,
 5,6,0,1,3,4,5,6,1,2,3,4,6,0,1,2,4,5,6,0,2,3,4,5,0,1,2,3,5,6,0,1,3,4,5,6,1,2,3,
 4,6,0,1,2,4,5,6,0,2,3,4,5,0,1,2,3,5,6,0,1,3,4,5,6,1,2,3,4,6,0,1,2,4,5,6,0,2,3,
 4,5,6,0,1,2,4,5,6,0,2,3,4,5,0,1,2,3,5,6,0,1,3,4,5,6,1,2,3,4,6,0,1,2,4,5,6,0,2,
 3,4,5,0,1,2,3,5,6,0,1,3,4,5,6,1,2,3,4,6,0,1,2,4,5,6,0,2,3,4,5,0,1,2,3,5,6,0,1,
 3,4,5,6,1,2,3,4,6,0,1,2,4,5,6,0,2,3,4,5,0,1,2,3,4,5,6,0,2,3,4,5,0,1,2,3,5,6,0,
 1,3,4,5,6,1,2,3,4,6,0,1,2,4,5,6,0,2,3,4,5,0,1,2,3,5,6,0,1,3,4,5,6,1,2,3,4,6,0,
 1,2,4,5,6,0,2,3,4,5,0,1,2,3,5,6,0,1,3,4,5,6,1,2,3,4,6,0,1,2,4,5,6,0,2,3,4,5,0,
 1,2,3,5,6,0,1,2,3,4,5,0,1,2,3,5,6,0,1,3,4,5,6,1,2,3,4,6,0,1,2,4,5,6,0,2,3,4,5,
 0,1,2,3,5,6,0,1,3,4,5,6,1,2,3,4,6,0,1,2,4,5,6,0,2,3,4,5,0,1,2,3,5,6,0,1,3,4,5,
 6,1,2,3,4,6,0,1,2,4,5,6,0,2,3,4,5,0,1,2,3,5,6,0,1,3,4,5,6,1,2,3,4,6,0,1,2,4,5,6,0);
dom:array[1..12] of shortint=(31,28,31,30,31,30,31,31,30,31,30,31);
word:array[0..6] of string=('sunday','monday','tuesday','wednesday','thursday','friday','saturday');
var c,y,m,d,now,i:longint;
begin
readln(y,m,d);
if((y mod 100=0)and(y mod 400=0))or
  ((y mod 100<>0)and(y mod 4=0))
  then dom[2]:=29;
now:=first[y];
for i:=1 to m-1 do
  now:=(now+dom[i])mod 7;
now:=(now+(d-1))mod 7;
writeln(word[now]);
//Zeller
if(m<3) then begin m:=m+12;y:=y-1;end;
c:=y div 100;
y:=y mod 100;
now:=y+y div 4+c div 4-c<<1+26*(m+1)div 10+d-1;
inc(now,(abs(now)div 7+1)*7);
writeln(word[now mod 7]);
end.

Freda's Chess

　 　 树状数组+先序遍历，想到正解结果忘记写一个点被改变好几次。可怜的WA10了，日。

program Chess;
CONST FileName='Chess';
      maxn=100000;
var u,Index,tot,n,m,i,a,b:longint;
    v,next:array[1..maxn*2] of longint;
    e,l,r,data:array[1..maxn] of longint;
    vis:array[1..maxn] of boolean;
    flag:char;
function  LowBit(x:longint):longint;
begin LowBit:=x and -x; end;
procedure add(i,x:longint);
          begin
          while i<=n do begin
            inc(data[i],x);
            i:=i+LowBit(i);
            end;
          end;
function  sum(i:longint):int64;
          begin
          sum:=0;
          while i>0 do begin
            inc(sum,data[i]);
            i:=i-Lowbit(i);
            end;
          end;
procedure build(a,b:longint);
          begin
          inc(tot);
          v[tot]:=b;
          next[tot]:=e[a];
          e[a]:=tot;
          end;
procedure DFS(u:longint);
          var i:longint;
          begin
          vis[u]:=true;
          inc(Index);
          l[u]:=Index;
          i:=e[u];
          while i<>0 do begin
            if not vis[v[i]]
              then DFS(v[i]);
            i:=next[i];
            end;
          r[u]:=Index;
          end;
BEGIN
readln(n);
for i:=1 to n-1 do
  begin
  readln(a,b);
  build(a,b);
  build(b,a);
  end;
DFS(1);
readln(m);
fillchar(vis,sizeof(vis),false);//vis=black
for i:=1 to m do
  begin
  readln(flag,u);
  case flag of
    'Q':writeln(r[u]-l[u]+1-sum(r[u])+sum(l[u]-1));
    'C':if vis[u]
          then begin add(l[u],-1);vis[u]:=false;end
          else begin add(l[u], 1);vis[u]:=true; end;
    end;
  end;
END.

Freda的城堡

　 　 writeln(n-1)有20分好开心。

　 　 如果点1不连边，其他点向树连一条边，那么最后这就是一刻树，对于每个点找出能使他连到树上以后满足最短路的边的条数，然后乘法原理。一开始SPFA写萎了T了4个点以为是数据猥琐，然后去找出题人（ym lyd大神），结果被人家发现是InQ忘记更新，然后存邻接表的数组开小了。

program castle;
CONST FileName='castle2';
      maxn=1100;
      p=(1<<31)-1;
var InQ,vis,vb:array[1..maxn] of boolean;
    num,pos,adjlist,d,Q,bian:array[1..maxn] of longint;
    v,w,next:array[1..maxn*maxn] of longint;
    cnt,x,y,l,tot,n,m,i,j:longint;
    ans:int64=1;
    map:array[1..maxn,1..maxn] of integer;
procedure save(x,y,l:longint);
          begin
          if (map[x][y]>0)and(map[x][y]<l)then
             l:=map[x][y];
          map[x][y]:=l;
          map[y][x]:=l;
          end;
procedure build(x,y,l:longint);
          begin
          inc(tot);
          v[tot]:=y;
          w[tot]:=l;
          next[tot]:=Adjlist[x];
          Adjlist[x]:=tot;
          end;
procedure SPFA;
          var h,t,i:longint;
          begin
          Q[1]:=1;d[1]:=0;InQ[1]:=true;h:=0;t:=1;
          for i:=2 to n do d[i]:=maxlongint;
          while h<>t do
            begin
            inc(h);if h>maxn then h:=1;
            i:=Adjlist[Q[h]];
            while i<>0 do begin
              if w[i]+d[Q[h]]<d[v[i]]
                then begin
                     d[v[i]]:=w[i]+d[Q[h]];
                     if not InQ[v[i]]
                       then begin
                            inc(t);if t>maxn then t:=1;
                            Q[t]:=v[i];inQ[v[i]]:=true;
                            end;
                     end;
              i:=next[i];
              end;
            InQ[Q[h]]:=false;
            end;
          end;
procedure swap(var a,b:longint);
var t:longint;begin t:=a;a:=b;b:=t;end;
procedure Qsort(l,r:longint);
          var i,j,mid:longint;
          begin
          i:=l;j:=r;mid:=d[(l+r)>>1];
          repeat
            while(i<r)and(d[i]<mid)do inc(i);
            while(l<j)and(mid<d[j])do dec(j);
            if i<=j then begin
                         swap(d[i],d[j]);
                         pos[num[i]]:=j;
                         pos[num[j]]:=i;
                         swap(num[i],num[j]);
                         inc(i);dec(j);
                         end;
          until i>j;
          if(i<r)then Qsort(i,r);
          if(l<j)then Qsort(l,j);
          end;
BEGIN
Assign(input,FileName+'.in');
Assign(output,FileName+'.out');
Reset(input);Rewrite(output);
readln(n,m);tot:=1;
for i:=1 to n do
  begin
  num[i]:=i;
  pos[i]:=i;
  end;
for i:=1 to m do
  begin
  readln(x,y,l);
  save(x,y,l);
  end;
for i:=1 to n do
  for j:=i+1 to n do
    if map[i][j]>0
      then begin
           build(i,j,map[i][j]);
           build(j,i,map[i][j]);
           end;
SPFA;Qsort(2,n);
for x:=2 to n do
  begin
  i:=Adjlist[num[x]];cnt:=0;
  while i<>0 do begin
    if d[pos[v[i]]]+w[i]=d[x]
      then inc(cnt);
    i:=next[i];end;
  ans:=(ans*cnt)mod p;
  if cnt=0 then writeln(x:5,'*');
  end;
writeln(ans);
Close(input);Close(output);
END.

总结

　 　 今天220是不难的，是可以rank29的，结果我拿了130，无奈的rank88。

  果然写暴力就有收获，还有就是想到正解的题目要多造数据。