Lưu ý: Các code mẫu dưới đây chỉ mang tính tham khảo và có thể không AC được bài tập này

Code mẫu của RR

{$R+,Q+}
uses math;
const
  so:array['0'..'7'] of longint=(0,1,2,3,4,5,6,7);
const
  FINP='';
  FOUT='';
  MAXN=100001;
var
  f1,f2:text;
  n:longint;
  kq:double;
  xb,yb,xm,ym:double;
  a:array[0..MAXN] of longint;
  left,right:array[0..MAXN,0..7] of longint;
  now:array[0..7] of longint;
procedure openF; inline;
begin
  assign(f1,FINP); reset(f1);
  assign(f2,FOUT); rewrite(f2);
end;
procedure closeF; inline;
begin
  close(f1); close(f2);
end;
procedure inp; inline;
var
  i,x:longint;
  ch:char;
begin
  readln(f1,xm,ym,xb,yb);
  readln(f1,n);
  for i:=1 to n do
    begin
      read(f1,ch);
      x:=so[ch];
      a[i]:=(a[i-1]+x) mod 8;
    end;
end;
function dist(x1,y1,x2,y2:double):double; inline;
begin
  dist:=sqrt(sqr(x2-x1)+sqr(y2-y1));
end;
procedure solve;
var
  i,c,cc:longint;
  xx,yy:double;
begin
  //Tinh vi tri hien tai cua khi, cap nhat cho ket qua
  fillchar(now,sizeof(now),0);
  for i:=1 to n do inc(now[a[i]]);
  xx:=xm-(now[1]-now[5]+now[3]-now[7])-(now[2]-now[6]);
  yy:=ym+(now[0]-now[4])+(now[1]-now[5]-now[3]+now[7]);
  kq:=dist(xx,yy,xb,yb);
  //Tinh mang left
  for i:=1 to n do
    begin
      left[i]:=left[i-1];
      inc(left[i,a[i]]);
    end;
  //Tinh mang right
  for i:=n downto 1 do
    begin
      right[i]:=right[i+1];
      inc(right[i,a[i]]);
    end;
  //Duyet vi tri thay the
  for i:=1 to n do
    for c:=1 to 7 do
      begin
        if (i=4) and (c=7) then
          begin
            write('');
          end;
        //Tinh so luot di chuyen theo moi huong
        for cc:=0 to 7 do now[cc]:=left[i-1,cc];
        for cc:=0 to 7 do inc(now[(cc+c) mod 8],right[i,cc]);
        //Tinh vi tri cua khi neu quay phim a[i] di c lan
        xx:=xm-(now[1]-now[5]+now[3]-now[7])-(now[2]-now[6]);
        yy:=ym+(now[0]-now[4])+(now[1]-now[5]-now[3]+now[7]);
        //Cap nhat lai ket qua
        kq:=min(dist(xx,yy,xb,yb),kq);
      end;
end;
procedure ans; inline;
begin
  writeln(f2,kq:0:10);
end;
begin
  openF;
  inp;
  solve;
  ans;
  closeF;
end.

Code mẫu của hieult

#include <cstdio>
//#include <conio.h>
#include <cmath>
#include <cstring>
#include <iostream>

class diem
{
     public:
     int x,y;
     diem(){};
     diem(int u,int v){ x = u;y=v;}

};


double kc(diem A,diem B)
{
      return sqrt(((long long)(A.x)-B.x)*((long long)A.x-B.x)+((long long)A.y-B.y)*(A.y-(long long)B.y));
}

    int a,b,X,Y,h[100010],f[9][100010],n,g[9];
    char s[100010];
    diem d[100010],finish,moi;
    double kq;

double min(double a,double b)
{
       if(a<b) return a;
       return b;
}

int main()
{
   // freopen("majmun.in.10","r",stdin);
    scanf("%d %d %d %d",&a,&b,&X,&Y);
    X = X-a;
    Y = Y-b;
    finish = diem(X,Y);
    scanf("%d %s",&n,s);
    h[0] = 0;
    d[0].x = 0; d[0].y = 0;
    for(int i = 1;i<=n;i++)
    {
        h[i] = (h[i-1]-s[i-1]+48);
        if(h[i]<0) h[i] += 8;
        if(h[i]>=1 && h[i]<=3) d[i].x = d[i-1].x+1;
        else if(h[i]>=5 && h[i]<=7) d[i].x = d[i-1].x-1;
        else d[i].x = d[i-1].x;
        if(h[i]==0 || h[i]==1 ||h[i] == 7) d[i].y = d[i-1].y+1 ;
        else if(h[i]>=3 && h[i]<=5) d[i].y = d[i-1].y-1;
        else d[i].y = d[i-1].y;
        //printf("%d %d %d\n",h[i],d[i].x,d[i].y);
    }

    kq = kc(d[n],finish);
    //printf("%d %d\n",d[n].x,d[n].y);
    for(int i = 0;i<=7;i++)
         f[i][n+1]=0;
    for(int i = n;i>=1;i--)
    {
         for(int j = 0;j<=7;j++)
         f[j][i] = f[j][i+1];
         f[h[i]][i] = f[h[i]][i+1]+1;
    }
    for(int i = 1;i<=n;i++)
    {
         for(int j = 1;j<=7;j++)
         {
              memset(g,0,sizeof(g));

              for(int k = 0;k<=7;k++)
                  g[k] = f[(k+j)%8][i];
              moi =  diem(d[i-1].x+g[1]+g[2]+g[3]-g[5]-g[6]-g[7],d[i-1].y+g[7]+g[0]+g[1]-g[3]-g[4]-g[5]);
              kq = min(kq,kc(moi,finish));
         }
    }
    printf("%lf",kq);
  // getch();

}