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 dx:array[1..4] of longint=(-1,0,1,0);
      dy:array[1..4] of longint=(0,1,0,-1);
      maxn=1010;
var a:array[1..maxn,1..maxn] of byte;
    m,n,num,min:longint;
    di:array[1..4,0..1] of longint;

procedure rf;
var i,j:longint;
begin
     readln(m,n);
     for i:=1 to m do
     begin
          for j:=1 to n do
              read(a[i,j]);
          readln;
     end;
     di[1,0]:=3; di[1,1]:=2;
     di[2,0]:=3; di[2,1]:=4;
     di[3,0]:=1; di[3,1]:=4;
     di[4,0]:=1; di[4,1]:=2;
end;

function check(x,y:longint):boolean;
begin
     check:=(x>0) and (y>0) and (x<=m) and (y<=n);
end;

procedure mov(j:longint;var x,y,z,pre:longint;var kt:boolean);
begin
     x:=x+dx[j]; y:=y+dy[j]; pre:=j;
     if check(x,y) then z:=di[j,a[x,y]]
     else kt:=false;
end;

procedure move(var x,y,z,pre:longint;var kt:boolean);
begin
     case z of
     1:begin
            if pre=3 then mov(2,x,y,z,pre,kt)
            else mov(1,x,y,z,pre,kt);
       end;
     2:begin
            if pre=1 then mov(2,x,y,z,pre,kt)
            else mov(3,x,y,z,pre,kt);
       end;
     3:begin
            if pre=1 then mov(4,x,y,z,pre,kt)
            else mov(3,x,y,z,pre,kt);
       end;
     4:begin
            if pre=3 then mov(4,x,y,z,pre,kt)
            else mov(1,x,y,z,pre,kt);
       end;
     end
end;

procedure pr;
var i,j,x,y,z,dem,pre:longint; kt:boolean;
begin
     min:=maxlongint; num:=0;
     for i:=1 to n do
     begin
          x:=1; y:=i; kt:=true;
          if a[x,y]=0 then z:=1 else z:=4;
          dem:=1; pre:=3;
          repeat
                move(x,y,z,pre,kt);
                if not kt then break;
                inc(dem);
                if (x=m) and ((z=2) or (z=3)) then break;
          until false;
          if kt then
          begin
               if dem<min then
               begin
                    min:=dem;
                    num:=1;
               end
               else
               begin
                    if dem=min then inc(num);
               end;
          end;
     end;
end;

procedure wf;
begin
     if num<>0 then write(min,' ',num)
     else write(0,' ',0);
end;

begin
     rf;
     pr;
     wf;
end.

Code mẫu của RR

{$R+,Q+}
program HAOI6000;
const
  FINP='';
  FOUT='';
  MAXN=1001;
  oo=2000001;
var
  xet:array[1..MAXN,1..MAXN,1..2] of byte;
  a:array[1..MAXN,1..MAXN] of byte;
  min,sl,m,n:longint;
procedure inp;
var
  f:text;
  i,j:longint;
begin
  assign(f,FINP); reset(f);
  readln(f,m,n);
  for i:=1 to m do
    for j:=1 to n do
      read(f,a[i,j]);
  close(f);
end;
procedure ans;
var
  f:text;
begin
  assign(f,FOUT); rewrite(f);
  if sl=0 then
    begin
      writeln(f,'0 0');
      close(f); halt;
    end;
  writeln(f,min,' ',sl);
  close(f);
end;
procedure find(i:longint);
var
  l,u,v,k:longint;
begin
  u:=1; v:=i; k:=1; l:=1;
  repeat
    inc(l); xet[u,v,k]:=1;
    if l>min then exit;
    if (a[u,v]=0) and (k=1) then
      begin
        if (v<n) and (xet[u,v+1,2-a[u,v+1]]=0) then
          begin
            inc(v);
            k:=2-a[u,v];
          end
        else if (u>1) and (xet[u-1,v,2]=0) then
          begin
            dec(u);
            k:=2;
          end
        else exit;
      end
    else if (a[u,v]=0) and (k=2) then
      begin
        if (v>1) and (xet[u,v-1,1+a[u,v-1]]=0) then
          begin
            dec(v);
            k:=1+a[u,v];
          end
        else if (u<m) and (xet[u+1,v,1]=0) then
          begin
            inc(u);
            k:=1;
          end
        else exit;
      end
    else if (a[u,v]=1) and (k=1) then
      begin
        if (v>1) and (xet[u,v-1,1+a[u,v-1]]=0) then
          begin
            dec(v);
            k:=1+a[u,v];
          end
        else if (u>1) and (xet[u-1,v,2]=0) then
          begin
            dec(u);
            k:=2;
          end
        else exit;
      end
    else if (a[u,v]=1) and (k=2) then
      begin
        if (v<n) and (xet[u,v+1,2-a[u,v+1]]=0) then
          begin
            inc(v);
            k:=2-a[u,v];
          end
        else if (u<m) and (xet[u+1,v,1]=0) then
          begin
            inc(u);
            k:=1;
          end
        else exit;
      end;
  until (u=m) and (k=2);
  if l<min then begin min:=l; sl:=1; end
  else if l=min then inc(sl);
end;
procedure solve;
var
  i:longint;
begin
  min:=oo;
  for i:=1 to n do
    find(i);
end;
begin
  inp;
  solve;
  ans;
end.

Code mẫu của hieult

#include <set>
#include <map>
#include <list>
#include <cmath>
#include <ctime>
#include <deque>
#include <queue>
#include <stack>
#include <bitset>
#include <cctype>
#include <cstdio>
#include <string>
#include <vector>
#include <cassert>
#include <cstdlib>
#include <cstring>
#include <sstream>
#include <iomanip>
#include <iostream>
#include <algorithm>

using namespace std;

typedef long long ll;
//typedef long double ld;
typedef double ld;
typedef unsigned int ui;
typedef unsigned long long ull;

#define Rep(i,n) for(__typeof(n) i = 0; i < (n); ++i)
#define Repd(i,n) for(__typeof(n) i = (n)-1; i >= 0; --i)
#define For(i,a,b) for(__typeof(b) i = (a); i <= (b); ++i)
#define Ford(i,a,b) for(__typeof(a) i = (a); i >= (b); --i)
#define Fit(i,v) for(__typeof((v).begin()) i = (v).begin(); i != (v).end(); ++i)
#define Fitd(i,v) for(__typeof((v).rbegin()) i = (v).rbegin(); i != (v).rend(); ++i)
#define mp make_pair
#define pb push_back
#define fi first
#define se second
#define sz(a) ((int)(a).size())
#define all(a) (a).begin(), (a).end()
#define ms(a,x) memset(a, x, sizeof(a))
#define nl puts("")
#define sp printf(" ")
#define ok puts("ok")
//#include <conio.h>

template<class F, class T> T convert(F a, int p = -1) { stringstream ss; if (p >= 0) ss << fixed << setprecision(p); ss << a; T r; ss >> r; return r; }
template<class T> void db(T a, int p = -1) { if (p >= 0) cout << fixed << setprecision(p); cout << a << " "; }
template<class T> T gcd(T a, T b) { T r; while (b != 0) { r = a % b; a = b; b = r; } return a; }
template<class T> T lcm(T a, T b) { return a / gcd(a, b) * b; }
template<class T> T sqr(T x) { return x * x; }
template<class T> T cube(T x) { return x * x * x; }
template<class T> struct Triple { T x, y, z; Triple() {} Triple(T _x, T _y, T _z) : x(_x), y(_y), z(_z) {} };
template<class T> Triple<T> euclid(T a, T b) { if (b == 0) return Triple<T>(1, 0, a); Triple<T> r = euclid(b, a % b); return Triple<T>(r.y, r.x - a / b * r.y, r.z); }
template<class T> int getbit(T s, int i) { return (s >> i) & 1; }
template<class T> T onbit(T s, int i) { return s | (T(1) << i); }
template<class T> T offbit(T s, int i) { return s & (~(T(1) << i)); }
template<class T> int cntbit(T s) { return s == 0 ? 0 : cntbit(s >> 1) + (s & 1); }
const int bfsz = 1 << 16; char bf[bfsz + 5]; int rsz = 0;int ptr = 0;
char gc() { if (rsz <= 0) { ptr = 0; rsz = fread(bf, 1, bfsz, stdin); if (rsz <= 0) return EOF; } --rsz; return bf[ptr++]; }
void ga(char &c) { c = EOF; while (!isalpha(c)) c = gc(); }
int gs(char s[]) { int l = 0; char c = gc(); while (isspace(c)) c = gc(); while (c != EOF && !isspace(c)) { s[l++] = c; c = gc(); } s[l] = '\0'; return l; }
template<class T> bool gi(T &v) {
    v = 0; char c = gc(); while (c != EOF && c != '-' && !isdigit(c)) c = gc(); if (c == EOF) return false; bool neg = c == '-'; if (neg) c = gc();
    while (isdigit(c)) { v = v * 10 + c - '0'; c = gc(); } if (neg) v = -v; return true;
}

const double PI = 2 * acos(0);
const string months[] = {"January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December"};
const int days[] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
const int dr[] = {-1, +0, +1, +0};
const int dc[] = {+0, +1, +0, -1};
const int inf = (int)1e9 + 5;
const ll linf = (ll)1e16 + 5;
const double eps = ld(1e-9);
const ll mod = 100000007;
typedef pair<int, int> II;

#define maxn 1005

int f[maxn][maxn][4] = {0};
int n, m, a[maxn][maxn];

int move[][2] = {2, 1, 2, 3, 0, 3, 0, 1};
bool thoaman(int r, int c){
    return (r >= 0 && r < n && c >= 0 && c < m);
}

Triple<int> que[maxn * maxn * 4];

int main(){
//    freopen("in.txt", "r", stdin);
//    freopen("out.txt", "w", stdout);
    gi(n); gi(m); Rep(i, n) Rep(j, m) gi(a[i][j]);
    int size = 0, r, c, rr, cc, id, id1, d;
    Rep(j, m){
        if(a[0][j] == 0){ 
            f[0][j][0] = 1;
            que[size++] = Triple<int>(0, j, 0);
        }
        else {
            f[0][j][3] = 1;
            que[size++] = Triple<int>(0, j, 3);
        }
    }
    Rep(i, size){
        r = que[i].x; c = que[i].y; id = que[i].z;
        For(t, id, id + 1){
            rr = r + dr[t % 4]; cc = c + dc[t % 4]; 
            if(thoaman(rr, cc)){
                id1 = move[(t) % 4][a[rr][cc]];
                if(!f[rr][cc][id1]){
                    f[rr][cc][id1] = f[r][c][id] + 1;
                    que[size++] = Triple<int>(rr, cc, id1);
                }
            }
        }
    }
    int res = inf, num = 0;
    Rep(j, m){
        For(t, 1, 2){
            if(f[n - 1][j][t] && f[n - 1][j][t] < res){
                res = f[n - 1][j][t];
                num = 1;
            }
            else if(f[n - 1][j][t] == res) num++;
        }
    }

    if(res < inf){
        printf("%d %d", res, num);
    }
    else printf("0 0");

}