Language: C++

#include <bits/stdc++.h>
 
using namespace std;
 
#define DEBUG(x) cerr<<#x<<": "<<x<<endl;
#define DEBUG_VEC(v) cerr<<#v<<":";for(int i=0;i<v.size();i++) cerr<<" "<<v[i]; cerr<<endl;
#define DEBUG_MAT(v) cerr<<#v<<endl;for(int i=0;i<v.size();i++){for(int j=0;j<v[i].size();j++) {cerr<<v[i][j]<<" ";}cerr<<endl;}
typedef long long ll;
#define int ll
 
#define vi vector<int>
#define vl vector<ll>
#define vii vector< vector<int> >
#define vll vector< vector<ll> >
#define vs vector<string>
#define pii pair<int,int>
#define pis pair<int,string>
#define psi pair<string,int>
#define pll pair<ll,ll>
template<class S, class T> pair<S, T> operator+(const pair<S, T> &s, const pair<S, T> &t) { return pair<S, T>(s.first + t.first, s.second + t.second); }
template<class S, class T> pair<S, T> operator-(const pair<S, T> &s, const pair<S, T> &t) { return pair<S, T>(s.first - t.first, s.second - t.second); }
template<class S, class T> ostream& operator<<(ostream& os, pair<S, T> p) { os << "(" << p.first << ", " << p.second << ")"; return os; }
#define X first
#define Y second
#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define rep1(i,n) for(int i=1;i<=(int)(n);i++)
#define rrep(i,n) for(int i=(int)(n)-1;i>=0;i--)
#define rrep1(i,n) for(int i=(int)(n);i>0;i--)
#define REP(i,a,b) for(int i=a;i<b;i++)
#define in(x, a, b) (a <= x && x < b)
#define all(c) c.begin(),c.end()
template<class T> bool chmax(T &a, const T &b) { if (a<b) { a = b; return 1; } return 0; }
template<class T> bool chmin(T &a, const T &b) { if (a>b) { a = b; return 1; } return 0; }
#define UNIQUE(v) v.erase(std::unique(v.begin(), v.end()), v.end());
const ll inf = 1000000001;
const ll INF = (ll)1e18 + 1;
const long double pi = 3.1415926535897932384626433832795028841971L;
#define Sp(p) cout<<setprecision(25)<< fixed<<p<<endl;
//int dx[4] = {1, 0, -1, 0}, dy[4] = {0, 1, 0, -1};
//int dx2[8] = { 1,1,0,-1,-1,-1,0,1 }, dy2[8] = { 0,1,1,1,0,-1,-1,-1 };
vi dx = {1, 0, -1, 0}, dy = {0, 1, 0, -1};
vi dx2 = { 1,1,0,-1,-1,-1,0,1 }, dy2 = { 0,1,1,1,0,-1,-1,-1 };
#define fio() cin.tie(0); ios::sync_with_stdio(false);
const ll MOD = 1000000007;
//const ll MOD = 998244353;
// #define mp make_pair
//#define endl '\n'

// 続きは今度書く
signed main() {
    fio();
    int n, m;
    cin >> n >> m;
    using P = pair<ll, pll>;
    vector<P> ylr(m), xud(n);
    set<ll> yst, xst;
    for (int i = -1; i <= 1; i++) {
        yst.insert(i); xst.insert(i);
    }
    yst.insert(-INF); yst.insert(INF);
    xst.insert(-INF); xst.insert(INF);

    map<ll, vector<pll>> y2lr, x2ud;

    rep (i, n) {
        cin >> xud[i].second.first >> xud[i].second.second >> xud[i].first;
        xst.insert(xud[i].first);
        yst.insert(xud[i].second.first); yst.insert(xud[i].second.second); 
    }
    rep (i, m) {
        cin >> ylr[i].first >> ylr[i].second.first >> ylr[i].second.second;
        yst.insert(ylr[i].first);
        xst.insert(ylr[i].second.first); xst.insert(ylr[i].second.second); 
    }

    vector<pll> lr, ud;
    auto itr = xst.begin();
    ll pre = *itr;
    xst.erase(itr);
    while (xst.size()) {
        auto itr = xst.begin();
        ll x = *itr;
        xst.erase(itr);
        lr.push_back(pll(pre, x));
        pre = x;
    }

    itr = yst.begin();
    pre = *itr;
    yst.erase(itr);
    while (yst.size()) {
        auto itr = yst.begin();
        ll y = *itr;
        yst.erase(itr);
        ud.push_back(pll(pre, y));
        pre = y;
    }

    // DEBUG_VEC(lr);
    // DEBUG_VEC(ud);

    int h = ud.size(), w = lr.size();
    int n = h * w;
    vii G(n);
    for (int i = 1; i < h - 1; i++) {
        for (int j = 1; j < w - 1; j++) {
            int u = i * w + j;
            rep (k, 4) {
                int ni = i + dy[k], nj = j + dx[k];
                
            }
        }
    }
}

Compiler output:
a.cc: In function 'int main()':
a.cc:103:9: error: redeclaration of 'll n'
  103 |     int n = h * w;
      |         ^
a.cc:52:9: note: 'll n' previously declared here
   52 |     int n, m;
      |         ^