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 maxn=100010;
var n,k:longint;
    x,y,a,d,f:array[1..maxn] of longint;
    maxcol:array[0..maxn] of longint;

procedure rf;
var i:longint;
begin
     read(n,k);
     for i:=1 to n do
     begin
          read(x[i],y[i],a[i]);
          d[i]:=i;
     end;
end;

procedure sort(l,r:longint);
var i,j,t,u,v:longint;
begin
     i:=l; j:=r; t:=x[(i+j) shr 1]; v:=y[(i+j) shr 1];
     repeat
           while (x[i]<t) or ((x[i]=t) and (y[i]<v)) do i:=i+1;
           while (x[j]>t) or ((x[j]=t) and (y[j]>v)) do j:=j-1;
           if i<=j then
           begin
                u:=d[i]; d[i]:=d[j]; d[j]:=u;
                u:=x[i]; x[i]:=x[j]; x[j]:=u;
                u:=y[i]; y[i]:=y[j]; y[j]:=u;
                u:=a[i]; a[i]:=a[j]; a[j]:=u;
                i:=i+1; j:=j-1;
           end;
     until i>j;
     if i<r then sort(i,r);
     if l<j then sort(l,j);
end;

function max(u,v:longint):longint;
begin
     if u>v then max:=u else max:=v;
end;

procedure pr;
var i,t,u,maxrow:longint;
begin
     sort(1,n);
     for i:=1 to n do f[i]:=-1;
     for i:=0 to maxn div 3 do maxcol[i]:=-1;
     for t:=1 to n do
         if d[t]=1 then break;
     f[t]:=a[t]; maxcol[y[t]]:=a[t]; maxrow:=a[t]; inc(t);
     while true do
     begin
          if x[t]=x[t-1] then
          begin
               if maxrow>=k then
                  f[t]:=max(f[t],maxrow-k+a[t]);
          end;
          if maxcol[y[t]]>=k then
             f[t]:=max(f[t],maxcol[y[t]]-k+a[t]);
          if x[t]=x[t-1] then maxrow:=max(maxrow,f[t])
          else maxrow:=f[t];
          maxcol[y[t]]:=max(maxcol[y[t]],f[t]);
          if d[t]=n then break;
          t:=t+1;
     end;
     writeln(f[t]);
end;

begin
     rf;
     pr;
end.

Code mẫu của happyboy99x

#include<cstdio>
#include<algorithm>
using namespace std;

const int N = 300000 + 5, XY = 100000 + 5, INF = 1000000000;
struct plant {
    int x, y, f, id;
    bool operator < (const plant &o) const {
        return x < o.x || x == o.x && y < o.y;
    }
} p[N];
int n, k, maxX[XY], maxY[XY], f[N];

void enter() {
    scanf("%d%d", &n, &k);
    for(int i = 1; i <= n; ++i) {
        scanf("%d%d%d", &p[i].x, &p[i].y, &p[i].f);
        p[i].id = i;
    }
}

void solve() {
    sort(p+1, p+n+1); f[0] = -INF;
    for(int i = 1; i <= n; ++i) {
        int id = p[i].id;
        f[id] = -INF; if(id == 1) f[id] = p[i].f;
        int xx = maxX[p[i].x], yy = maxY[p[i].y];
        if(f[xx] >= k && f[xx] - k + p[i].f > f[id]) f[id] = f[xx] - k + p[i].f;
        if(f[yy] >= k && f[yy] - k + p[i].f > f[id]) f[id] = f[yy] - k + p[i].f;
        if(f[id] > f[xx]) maxX[p[i].x] = id;
        if(f[id] > f[yy]) maxY[p[i].y] = id;
    }
    printf("%d\n", f[n]);
}

int main() {
    enter();
    solve();
    return 0;
}

Code mẫu của ladpro98

program baricavn;//dp
uses    math;
type    e=record
        x,y,p,s:longint;
        end;
const   maxn=300005;
        maxV=100005;
        fi='';
var     a:array[1..maxn] of e;
        maxCol,maxRow:array[0..maxV] of longint;
        n,k:longint;

procedure input;
var     inp:text;
        i:longint;
begin
        assign(inp,fi);
        reset(inp);
        readln(inp,n,k);
        for i:=1 to n do
        begin
                readln(inp,a[i].x,a[i].y,a[i].s);
                a[i].p:=i;
        end;
        close(inp);
end;

procedure swap(i,j:longint);
var     t:e;
begin
        t:=a[i];
        a[i]:=a[j];
        a[j]:=t;
end;


procedure sort(l,r:longint);
var     i,j:longint;
        p:e;
begin
        if l>=r then exit;
        i:=l;j:=r;
        p:=a[random(r-l+1)+l];
        repeat
                while (a[i].x<p.x) or ((a[i].x=p.x) and (a[i].y<p.y)) do inc(i);
                while (a[j].x>p.x) or ((a[j].x=p.x) and (a[j].y>p.y)) do dec(j);
                if i<=j then
                begin
                        if i<j then swap(i,j);
                        inc(i);
                        dec(j);
                end;
        until i>j;
        sort(l,j);
        sort(i,r);
end;

procedure dp;
var     j,i,t,lx,ly:longint;
begin
        for j:=1 to n do
        if a[j].p=1 then
        begin
                maxRow[a[j].x]:=a[j].s;
                maxCol[a[j].y]:=a[j].s;
                lx:=a[j].x;ly:=a[j].y;
                for i:=j+1 to n do
                if (a[i].x>=lx) and (a[i].y>=ly) then
                if max(maxRow[a[i].x],maxCol[a[i].y])>=k then
                begin
                        t:=max(maxRow[a[i].x],maxCol[a[i].y])-k+a[i].s;
                        if a[i].p=n then
                        begin
                                writeln(t);
                                exit;
                        end;
                        maxRow[a[i].x]:=max(maxRow[a[i].x],t);
                        maxCol[a[i].y]:=max(maxCol[a[i].y],t);
                end;
        end;
end;

begin
        input;
        sort(1,n);
        dp;
end.

Code mẫu của RR

#include <cstdio>
#include <cstdlib>
#include <algorithm>
#include <set>

#define MAXN 300111
#define FOR(i,a,b) for(long i=a; i<=b; i++)
#define S set< pair<long,long> >
#define FORS(s,i) for(S::iterator i=s.begin(); i!=s.end(); i++)
#define MP make_pair

using namespace std;
long n,k,targetu,targetv,startu,startv,maxX[MAXN],maxY[MAXN],f[MAXN];
pair< pair<long,long>,long> a[MAXN];
S s;

void inp() {
     scanf("%ld %ld",&n,&k);
     FOR(i,1,n)
       scanf("%ld %ld %ld",&a[i].first.first,&a[i].first.second,&a[i].second);
}

void RR() {
     //Roi rac hoa theo truc X
     FOR(i,1,n)
       s.insert(MP(a[i].first.first,i));
     long now=s.begin()->first,ind=1;
     a[s.begin()->second].first.first=1;
     FORS(s,i)
     if (i!=s.begin()) {
                       if (i->first!=now) {
                                          ind++;
                                          now=i->first;
                       }
                       a[i->second].first.first=ind;
     }
     //Roi rac hoa theo truc Y
     s.clear();
     FOR(i,1,n) 
       s.insert(MP(a[i].first.second,i));
     now=s.begin()->first; ind=1;
     a[s.begin()->second].first.second=1;
     FORS(s,i)
     if (i!=s.begin()) {
                       if (i->first!=now) {
                                          ind++;
                                          now=i->first;
                       }
                       a[i->second].first.second=ind;
     }
}

void solve() {
     targetu=a[n].first.first;
     targetv=a[n].first.second;
     startu=a[1].first.first;
     startv=a[1].first.second;

     sort(a+1,a+n+1);
     FOR(i,1,n) {
                if (a[i].first.first==startu&&a[i].first.second==startv) {
                       f[i]=a[i].second;
                       maxX[a[i].first.first]=f[i];
                       maxY[a[i].first.second]=f[i];
                } else {
                       long temp=max(maxX[a[i].first.first],maxY[a[i].first.second])-k;
                       if (temp>=0) temp+=a[i].second; else temp=0;
                       f[i]=temp;
                       maxX[a[i].first.first]>?=f[i];
                       maxY[a[i].first.second]>?=f[i];
                }
     }
     FOR(i,1,n)
       if (a[i].first.first==targetu&&a[i].first.second==targetv)
         printf("%ld\n",f[i]);
}

int main() {
    #ifdef DEBUG
      freopen("input.txt","r",stdin);
      freopen("output.txt","w",stdout);
    #endif
    inp();
    RR();
    solve();
    return 0;
}

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 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 = 1e-9;
const ll mod = 100000007;
typedef pair<int, int> II;

#define maxn 300005

pair<II, II> A[maxn];
int n, k, fx[maxn], fy[maxn], f[maxn];

int main() {
//    freopen("in.txt", "r", stdin);
//    freopen("out.txt", "w", stdout);
    ms(f, -1); ms(fx, -1); ms(fy, -1);
    gi(n); gi(k);
    Rep(i, n){
        gi(A[i].fi.fi); gi(A[i].fi.se); gi(A[i].se.fi);
        A[i].se.se = i + 1;
    }
    sort(A, A + n);
    bool flag = false;
    int x, y, num, id, t;
    Rep(i, n){

        if(!flag && A[i].se.se != 1) continue;
        x = A[i].fi.fi; y = A[i].fi.se; num = A[i].se.fi; id = A[i].se.se;
        if(A[i].se.se == 1){
            flag = true;
            fx[x] = max(fx[x], num);
            fy[y] = max(fy[y], num);
            continue;
        }
        t = max(fx[x], fy[y]);
        if(t < k) continue;
        fx[x] = max(fx[x], t - k + num);
        fy[y] = max(fy[y], t - k + num);
        if(id == n){
            printf("%d", t - k + num);
            return 0;
        }
    }
}

Code mẫu của ll931110

{$MODE DELPHI}
program BARICAVN;
uses math;
const
  input  = '';
  output = '';
  maxn = 300000;
  maxt = 100000;
type
  rec = record
    x,y,val,pos: integer;
  end;
var
  a: array[1..maxn] of rec;
  maxx,maxy: array[0..maxt] of integer;
  n,k: integer;

procedure init;
var
  f: text;
  i: integer;
begin
  assign(f, input);
    reset(f);

  readln(f, n, k);
  for i := 1 to n do
    begin
      readln(f, a[i].x,a[i].y,a[i].val);
      a[i].pos := i;
    end;

  close(f);
end;

procedure swap(var u,v: rec);
var
  z: rec;
begin
  z := u;  u := v;  v := z;
end;

function lower(u,v: rec): boolean;
begin
  lower := (u.x < v.x) or ((u.x = v.x) and (u.y < v.y));
end;

procedure quicksort;

  procedure par(l,h: integer);
  var
    i,j: integer;
    p: rec;
  begin
    if l >= h then exit;
    i := l; j := h; p := a[random(h - l + 1) + l];

    repeat
      while lower(a[i],p) do inc(i);
      while lower(p,a[j]) do dec(j);

      if i <= j then
        begin
          if i < j then swap(a[i],a[j]);
          inc(i);
          dec(j);
        end;
    until i > j;

    par(l,j);
    par(i,h);
  end;

begin
  par(1,n);
end;

procedure solve;
var
  f: text;
  i,t: integer;
begin
  for i := 0 to maxt do
    begin
      maxx[i] := -maxn;
      maxy[i] := -maxn;
    end;

  i := 1;
  while a[i].pos <> 1 do inc(i);
  maxx[a[i].x] := a[i].val;
  maxy[a[i].y] := a[i].val;

  repeat
    inc(i);
    t := max(maxx[a[i].x],maxy[a[i].y]);
    if t >= k then t := t - k + a[i].val;
    if maxx[a[i].x] < t then maxx[a[i].x] := t;
    if maxy[a[i].y] < t then maxy[a[i].y] := t;
  until a[i].pos = n;

  assign(f, output);
    rewrite(f);
    writeln(f, t);
  close(f);
end;

begin
  init;
  quicksort;
  solve;
end.