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

Code mẫu của flashmt

const fi='';
      oo=1000000000;
      dx:array[1..4] of longint=(-1,0,1,0);
      dy:array[1..4] of longint=(0,1,0,-1);
      maxm=2500;
var m,n,f,nh:longint;
    ngang,doc:array[1..maxm,1..10] of longint;
    pos,h,p,d,cur:array[1..maxm*10] of longint;
    free:array[1..maxm*10] of boolean;
    stt:array[0..maxm,1..10] of longint;
    a,c:array[1..maxm*10*8] of longint;

function calc(i,j,ii,jj:longint):longint;
begin
     if i=ii then
     begin
          if j<jj then calc:=ngang[i,j]
          else calc:=ngang[i,jj];
     end
     else
     begin
          if i<ii then calc:=doc[ii,j]
          else calc:=doc[i,j];
     end;
end;

procedure rf;
var i,j,dem,k,x,y,ii,jj:longint;
begin
     read(m,n);
     for i:=1 to m do
     begin
          for j:=1 to n do read(doc[i,j]);
          for j:=1 to n-1 do read(ngang[i,j]);
     end;
     dem:=1;
     for i:=1 to m do
         for j:=1 to n do
         begin
              inc(dem);
              stt[i,j]:=dem;
         end;
     pos[1]:=1; cur[1]:=n;
     for i:=1 to n do
     begin
          a[i]:=stt[1,i];
          c[i]:=doc[1,i];
          stt[0,i]:=1;
     end;
     for i:=1 to m do
         for j:=1 to n do
         begin
              x:=stt[i,j];
              pos[x]:=cur[x-1]+1; cur[x]:=cur[x-1];
              for k:=1 to 4 do
              begin
                   ii:=i+dx[k]; jj:=j+dy[k];
                   if (ii<=m) and (jj>0) and (jj<=n) then
                   begin
                        y:=stt[ii,jj];
                        inc(cur[x]);
                        a[cur[x]]:=y;
                        c[cur[x]]:=calc(i,j,ii,jj);
                   end;
              end;
         end;
     f:=x;
     pos[f+1]:=cur[f]+1;
end;

procedure update(x:longint);
var cha,con:longint;
begin
     con:=p[x];
     if con=0 then
     begin
          inc(nh); con:=nh;
     end;
     cha:=con shr 1;
     while (cha>0) and (d[h[cha]]>d[x]) do
     begin
          h[con]:=h[cha];
          p[h[con]]:=con;
          con:=cha;
          cha:=con shr 1;
     end;
     h[con]:=x; p[x]:=con;
end;

function pop:longint;
var x,cha,con:longint;
begin
     pop:=h[1];
     x:=h[nh]; dec(nh);
     cha:=1; con:=2;
     while (con<=nh) do
     begin
          if (con<nh) and (d[h[con+1]]<d[h[con]]) then inc(con);
          if d[x]<=d[h[con]] then break;
          h[cha]:=h[con];
          p[h[cha]]:=cha;
          cha:=con;
          con:=cha shl 1;
     end;
     h[cha]:=x; p[x]:=cha;
end;

procedure pr;
var i,x,y:longint;
begin
     for i:=1 to f do
     begin
          free[i]:=true; d[i]:=oo;
     end;
     d[1]:=0;
     update(1);
     repeat
           x:=pop; free[x]:=false;
           if x=f then break;
           for i:=pos[x] to pos[x+1]-1 do
           begin
                y:=a[i];
                if free[y] and (d[y]>d[x]+c[i]) then
                begin
                     d[y]:=d[x]+c[i];
                     update(y);
                end;
           end;
     until nh=0;
     writeln(d[f]);
end;

begin
     assign(input,fi); reset(input);
     rf;
     pr;
     close(input);
end.

Code mẫu của happyboy99x

#include <algorithm>
#include <bitset>
#include <cctype>
#include <cfloat>
#include <climits>
#include <cmath>
#include <complex>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <deque>
#include <functional>
#include <iostream>
#include <list>
#include <map>
#include <numeric>
#include <queue>
#include <set>
#include <stack>
#include <string>
#include <utility>
#include <vector>
using namespace std;

typedef pair<int, int> ii;
typedef vector<ii> vii;
typedef vector<vii> vvii;
typedef vector<int> vi;
typedef vector<vi> vvi;

#define sz(a) int((a).size())
#define fi first
#define se second
#define pb push_back
#define mp make_pair
#define all(c) (c).begin(), (c).end()
#define tr(c,i) for(typeof((c).begin()) i = (c).begin(), _e = (c).end(); i != _e; ++i)
#define present(c,x) ((c).find(x) != (c).end())
#define cpresent(c,x) (find(all(c),x) != (c).end())
#define rep(i,n) for(int i = 0, _n = (n); i < _n; ++i)
#define repd(i,n) for(int i = (n)-1; i >= 0; --i )
#define fo(i,a,b) for(int i = (a), _b = (b); i <= _b; ++i)
#define fod(i,a,b) for(int i = (a), _b = (b); i >= _b; --i)
#define hash(a,b) (((a)-1)*n+(b))

#define INF 1000000000/*(int(1e9))*/
#define M 2500
#define N 20

int a[2*M][N],m,n,d[M*N];
//long long d[M*N];
vvii g;

void dijkstra() {
    fill(d+1,d+m*n+1,INF);
    priority_queue< ii, vii, greater<ii> > qu; qu.push(ii(0, 0));
    while(!qu.empty()) {
        ii top = qu.top(); qu.pop();
        int du = top.fi, u = top.se; 
        if( du > d[u] ) continue;
        tr(g[u],it) {
            int v = it->fi, l = it->se;
            if( d[v] > du + l ) qu.push(ii(d[v] = du + l, v));
        }
    }
}

int main() {
#ifndef ONLINE_JUDGE
    freopen( "input.txt", "r", stdin );
    //freopen( "output.txt", "w", stdout );
#endif
    scanf("%d%d",&m,&n);
    fo(i,1,2*m) fo(j,1,n-1+i%2) scanf("%d",&a[i][j]);
    g.resize(m*n+1);
    fo(i,1,m) fo(j,1,n) {
        int p = hash(i,j);
        if(i != m) g[p].pb(ii(hash(i+1,j), a[i+i+1][j]));
        if(i != 1) g[p].pb(ii(hash(i-1,j), a[i+i-1][j]));
        if(j != n) g[p].pb(ii(hash(i,j+1), a[i+i][j]));
        if(j != 1) g[p].pb(ii(hash(i,j-1), a[i+i][j-1]));
    }
    fo(i,1,n) g[0].pb(mp(i, a[1][i]));
#ifndef ONLINE_JUDGE
    rep(i,m*n+1) {
        printf("%d", i);
        tr(g[i], it) printf(" (%d %d)", it->fi, it->se);
        putchar(10);
    }
#endif
    dijkstra(); printf("%d\n", d[m*n]);
    return 0;
}

Code mẫu của ladpro98

{$MODE OBJFPC}
program binladen;
uses    math;
const   maxn=11;
        maxm=2223;
        oo=trunc(1e9);
        up=1;r=4;down=3;l=2;
        dx:array[1..4] of longint = (-1,0,1,0);
        dy:array[1..4] of longint = (0,1,0,-1);
        fi='';
type    e=record
        x,y:longint;
        end;
var     m,n,nh:longint;
        pos,d:array[0..maxm,1..maxn] of longint;
        h:array[1..maxm*maxn] of e;
        a:array[0..maxm,0..maxn,1..4] of longint;

procedure input;
var     inp:text;
        i,j,w:longint;
begin
        assign(inp,fi);reset(inp);
        readln(inp,m,n);
        for i:=1 to 2*m do
        begin
                if odd(i) then
                for j:=1 to n do begin
                        read(inp,w);
                        a[i div 2+1,j,up]:=w;
                        a[i div 2,j,down]:=w;
                end
                else
                for j:=1 to n-1 do begin
                        read(inp,w);
                        a[i div 2,j,l]:=w;
                        a[i div 2,j+1,r]:=w;
                end;
        end;
        close(inp);
end;

procedure update(u,v:longint);
var     p,c:longint;
begin
        c:=pos[u,v];
        if c=0 then
        begin
                inc(nh);
                c:=nh;
        end;
        repeat
                p:=c shr 1;
                if (p=0) or (d[h[p].x,h[p].y]<=d[u,v]) then break;
                h[c]:=h[p];
                pos[h[c].x,h[c].y]:=c;
                c:=p;
        until false;
        h[c].x:=u;h[c].y:=v;
        pos[u,v]:=c;
end;

function extract:e;
var     p,c:longint;
        v:e;
begin
        result:=h[1];
        v:=h[nh];
        dec(nh);
        p:=1;
        repeat
                c:=2*p;
                if (c<nh) and (d[h[c+1].x,h[c+1].y]<d[h[c].x,h[c].y]) then inc(c);
                if (c>nh) or (d[h[c].x,h[c].y]>=d[v.x,v.y]) then break;
                h[p]:=h[c];
                pos[h[p].x,h[p].y]:=p;
                p:=c;
        until false;
        h[p]:=v;
        pos[v.x,v.y]:=p;
end;

procedure dijkstra;
var     i,j,x,y,w:longint;
        u:e;
begin
        for i:=1 to m do for j:=1 to n do d[i,j]:=oo;
        for j:=1 to n do update(0,j);
        repeat
                u:=extract;
                for i:=1 to 4 do
                begin
                        x:=u.x+dx[i];
                        y:=u.y+dy[i];
                        if (x<1) or (y<1) or (x>m) or (y>n) then continue;
                        w:=a[u.x,u.y,i];
                        if d[x,y]>d[u.x,u.y]+w then
                        begin
                                d[x,y]:=d[u.x,u.y]+w;
                                update(x,y);
                        end;
                end;
        until nh=0;
end;

begin
        input;
        dijkstra;
        write(d[m,n]);
end.

Code mẫu của RR

{$R+,Q+}
const
  FINP='';
  FOUT='';
  MAXN=20;
  MAXM=3000;
  oo=100000000;
var
  m,n,hsize:longint;
  hpos,d:array[1..MAXM,1..MAXN] of longint;
  hu,hv:array[1..MAXN*MAXM] of longint;
  cx,cs:array[1..MAXM,1..MAXN] of longint;
procedure inp;
var
  i,j:longint;
begin
  assign(input,FINP); reset(input);
  readln(m,n);
  for i:=1 to m do
    begin
      for j:=1 to n do read(cx[i,j]);
      for j:=2 to n do read(cs[i,j]);
    end;
  close(input);
end;
procedure swap(var a,b:longint);
var
  temp:longint;
begin
  temp:=a; a:=b; b:=temp;
end;
procedure downHeap(i:longint);
var
  j:longint;
begin
  j:=i shl 1;
  while (j<=hsize) do
    begin
      if (j<hsize) and (d[hu[j+1],hv[j+1]]<d[hu[j],hv[j]]) then inc(j);
      if d[hu[j],hv[j]]<d[hu[i],hv[i]] then
        begin
          swap(hpos[hu[j],hv[j]],hpos[hu[i],hv[i]]);
          swap(hu[i],hu[j]);
          swap(hv[i],hv[j]);
        end;
      i:=j; j:=i shl 1;
    end;
end;
procedure upHeap(i:longint);
var
  j:longint;
begin
  j:=i shr 1;
  while (i>1) and (d[hu[j],hv[j]]>d[hu[i],hv[i]]) do
    begin
      swap(hpos[hu[i],hv[i]],hpos[hu[j],hv[j]]);
      swap(hu[i],hu[j]);
      swap(hv[i],hv[j]);
      i:=j; j:=i shr 1;
    end;
end;
procedure push(u,v:longint);
begin
  inc(hsize);
  hu[hsize]:=u; hv[hsize]:=v;
  hpos[u,v]:=hsize;
  upHeap(hsize);
end;
procedure pop(var u,v:longint);
begin
  u:=hu[1]; v:=hv[1];
  swap(hpos[hu[1],hv[1]],hpos[hu[hsize],hv[hsize]]);
  swap(hu[1],hu[hsize]);
  swap(hv[1],hv[hsize]);
  dec(hsize);
  downHeap(1);
end;
procedure solve;
var
  u,v,i:longint;
begin
  hsize:=0;
  for u:=1 to m do
  for v:=1 to n do
    d[u,v]:=oo;
  for i:=1 to n do
    begin
      d[1,i]:=cx[1,i];
      push(1,i);
    end;
  while hsize>0 do
    begin
      pop(u,v);
      if (u=m) and (v=n) then
        begin
          assign(output,FOUT); rewrite(output);
          writeln(d[u,v]);
          close(output);
          halt;
        end;
      if (u<m) and (d[u+1,v]>d[u,v]+cx[u+1,v]) then
        begin
          d[u+1,v]:=d[u,v]+cx[u+1,v];
          if hpos[u+1,v]=0 then push(u+1,v)
          else upHeap(hpos[u+1,v]);
        end;
      if (u>1) and (d[u-1,v]>d[u,v]+cx[u,v]) then
        begin
          d[u-1,v]:=d[u,v]+cx[u,v];
          if hpos[u-1,v]=0 then push(u-1,v)
          else upHeap(hpos[u-1,v]);
        end;
      if (v>1) and (d[u,v-1]>d[u,v]+cs[u,v]) then
        begin
          d[u,v-1]:=d[u,v]+cs[u,v];
          if hpos[u,v-1]=0 then push(u,v-1)
          else upHeap(hpos[u,v-1]);
        end;
      if (v<n) and (d[u,v+1]>d[u,v]+cs[u,v+1]) then
        begin
          d[u,v+1]:=d[u,v]+cs[u,v+1];
          if hpos[u,v+1]=0 then push(u,v+1)
          else upHeap(hpos[u,v+1]);
        end;
    end;
end;
begin
  inp;
  solve;
end.

Code mẫu của ll931110

{$MODE DELPHI}
Program BINLADEN;
  Const
    input  = '';
    output = '';
    maxm = 2500;
    maxn = 12;
    maxv = 100000000;
    maxk = 25000;
  Type
    rec = record
      x,y: integer;
    end;
  Var
    d,a,c,pos: array[0..maxm,0..maxn] of integer;
    heap: array[1..maxk] of rec;
    free: array[0..maxm,0..maxn] of boolean;
    m,n: integer;
    p,q: integer;
    nHeap: integer;

Procedure init;
  Var
    f: text;
    i,j: integer;
  Begin
    Assign(f, input);
      Reset(f);

    For i:= 0 to maxm do
      For j:= 0 to maxn do
        Begin
          a[i,j]:= maxv;
          c[i,j]:= maxv;
        End;

    Readln(f, m, n);
    For i:= 1 to m do
      Begin
        For j:= 1 to n do read(f, a[i,j]);
        For j:= 1 to n - 1 do read(f, c[i,j]);
      End;

    Close(f);
  End;

Procedure update(u,v: integer);
  Var
    ch,pr: integer;
  Begin
    ch:= pos[u,v];
    If ch = 0 then
      Begin
        inc(nHeap);
        ch:= nHeap;
      End;

    pr:= ch div 2;
    While (pr > 0) and
      (d[heap[pr].x,heap[pr].y] > d[u,v]) do
        Begin
          heap[ch]:= heap[pr];
          pos[heap[ch].x,heap[ch].y]:= ch;

          ch:= pr;
          pr:= ch div 2;
        End;

      heap[ch].x:= u;
      heap[ch].y:= v;
      pos[u,v]:= ch;
  End;

Procedure pop;
  Var
    u,v,r,k: integer;
  Begin
    p:= heap[1].x;
    q:= heap[1].y;

    u:= heap[nHeap].x;
    v:= heap[nHeap].y;
    dec(nHeap);

    r:= 1;
    While r * 2 <= nHeap do
      Begin
        k:= r * 2;
        If (k < nHeap) and
          (d[heap[k + 1].x,heap[k + 1].y] < d[heap[k].x,heap[k].y]) then inc(k);

        If d[heap[k].x,heap[k].y] >= d[u,v] then break;

        heap[r]:= heap[k];
        pos[heap[r].x,heap[r].y]:= r;
        r:= k;
      End;

    heap[r].x:= u;
    heap[r].y:= v;
    pos[u,v]:= r;
  End;

Procedure Dijkstra;
  Var
    i,j: integer;
  Begin
    Fillchar(free, sizeof(free), false);
    For i:= 1 to m do
      For j:= 1 to n do free[i,j]:= true;

    Fillchar(pos, sizeof(pos), 0);
    nHeap:= 0;

    For i:= 0 to maxm do
      For j:= 0 to maxn do d[i,j]:= maxv;

    For i:= 1 to n do
      Begin
        d[1,i]:= a[1,i];
        update(1,i);
      End;

    Repeat
      pop;
      If (p = m) and (q = n) then break;

      free[p,q]:= false;
      If free[p + 1,q] and (d[p + 1,q] > d[p,q] + a[p + 1,q]) then
        Begin
          d[p + 1,q]:= d[p,q] + a[p + 1,q];
          update(p + 1,q);
        End;

      If free[p - 1,q] and (d[p - 1,q] > d[p,q] + a[p,q]) then
        Begin
          d[p - 1,q]:= d[p,q] + a[p,q];
          update(p - 1,q);
        End;

      If free[p,q + 1] and (d[p,q + 1] > d[p,q] + c[p,q]) then
        Begin
          d[p,q + 1]:= d[p,q] + c[p,q];
          update(p,q + 1);
        End;

      If free[p,q - 1] and (d[p,q - 1] > d[p,q] + c[p,q - 1]) then
        Begin
          d[p,q - 1]:= d[p,q] + c[p,q - 1];
          update(p,q - 1);
        End;
    Until nHeap = 0;
  End;

Procedure printresult;
  Var
    f: text;
  Begin
    Assign(f, output);
      Rewrite(f);
      Writeln(f, d[m,n]);
    Close(f);
  End;

Begin
  init;
  Dijkstra;
  printresult;
End.