Language: C++

// #pragma GCC target ("avx")
// #pragma GCC optimize("Ofast")
// #pragma GCC optimize("unroll-loops")
// #pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#include <bits/stdc++.h>
using namespace std;
#define int long long
// #define endl '\n'

#pragma region TEMPLATE

/* TYPE */
typedef long long ll;       typedef long double ld;
typedef pair<int, int> pii; typedef pair<ll, ll> pll;
typedef vector<pii> vpii;   typedef vector<pll> vpll;
typedef vector<int> vi;     typedef vector<ll> vl;
typedef vector<string> vst; typedef vector<bool> vb;
typedef vector<ld> vld;     typedef vector<vector<int>> vvi;
template<typename T, typename Cmp = less<>> using prique = priority_queue<T, vector<T>, Cmp>;
template<typename T> using prique_r = prique<T, greater<>>;
/* CONSTANT */
#define ln '\n'
const int INF = 1 << 30;    const ll INFF = 1LL << 60;  const string ALPHABET = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
const int MOD = 1e9 + 7;    const int MODD = 998244353; const string alphabet = "abcdefghi
pqrstuvwxyz";
const double EPS = 1e-9;    const ld PI = 3.14159265358979323846264338327950288;
// const int dx[] = { 1, 0, -1,  0,  1, -1, -1, 1, 0 };
// const int dy[] = { 0, 1,  0, -1, -1, -1,  1, 1, 0 };
/* CONTAINER */
#define PB              emplace_back
#define ALL(v)          (v).begin(), (v).end()
#define RALL(v)         (v).rbegin(), (v).rend()
#define SORT(v)         sort(ALL(v))
#define RSORT(v)        sort(RALL(v))
#define LESS(x, val)    (lower_bound(x.begin(), x.end(), val) - x.begin())
#define LEQ(x, val)     (upper_bound(x.begin(), x.end(), val) - x.begin())
#define GREATER(x, val) (int)(x).size() - LEQ((x), (val))
#define GEQ(x, val)     (int)(x).size() - LESS((x), (val))
#define UNIQUE(v)       sort(ALL(v)); (v).erase(unique(ALL(v)), (v).end())
template<typename T> vector<T> make_v(size_t a) { return vector<T>(a); }
template<typename T, typename... Ts> auto make_v(size_t a, Ts... ts) { return vector<decltype(make_v<T>(ts...))>(a, make_v<T>(ts...)); }
template<typename T, typename U, typename... V> enable_if_t<is_same<T, U>::value != 0> fill_v(U &u, const V... v) { u = U(v...); }
template<typename T, typename U, typename... V> enable_if_t<is_same<T, U>::value == 0> fill_v(U &u, const V... v) { for (auto &e : u) fill_v<T>(e, v...); }
/* LOOP */
#define _overload3(_1, _2, _3, name, ...) name
#define _REP(i, n)      REPI(i, 0, n)
#define REPI(i, a, b)   for (ll i = (ll)a; i < (ll)b; ++i)
#define REP(...)        _overload3(__VA_ARGS__, REPI, _REP,)(__VA_ARGS__)
#define _RREP(i, n)     RREPI(i, n, 0)
#define RREPI(i, a, b)  for (ll i = (ll)a; i >= (ll)b; --i)
#define RREP(...)       _overload3(__VA_ARGS__, RREPI, _RREP,)(__VA_ARGS__)
#define EACH(e, v)      for (auto& e : v)
#define PERM(v)         sort(ALL(v)); for (bool c##p = true; c##p; c##p = next_permutation(ALL(v)))
/* INPUT */
template<typename T> void SSS(T& t) { cin >> t; }
template<typename Head, typename... Tail> void SSS(Head&& head, Tail&&... tail) { cin >> head; SSS(tail...); }
#define SS(T, ...)      T __VA_ARGS__; SSS(__VA_ARGS__);
#define SV(T, v, n)     vector<T> v(n); for (auto& i : v) cin >> i;
#define SVV(T, v, n, m) vector<vector<T>> v(n, vector<T>(m)); for (auto& r : v) for (auto& i : r) cin >> i;
/* OUTPUT */
// PROTOTYPE DECLARATION
template<typename T, typename U> ostream &operator<<(ostream &os, const pair<T, U> &j);
template<typename... T> ostream &operator<<(ostream &os, const tuple<T...> &t);
template<class C, enable_if_t<!is_same<C, string>::value, decltype(declval<const C &>().begin(), nullptr)> = nullptr> ostream& operator<<(ostream &os, const C &c);
template<typename T> ostream &operator<<(ostream &os, const stack<T> &j);
template<typename T> ostream &operator<<(ostream &os, const queue<T> &j);
template<typename T, typename C, typename Cmp> ostream &operator<<(ostream &os, const priority_queue<T, C, Cmp> &j);
// IMPLEMENTATION
template<typename T, typename U> ostream &operator<<(ostream &os, const pair<T, U> &j) { return os << '{' << j.first << ", " << j.second << '}'; }
template<size_t num = 0, typename... T> enable_if_t<num == sizeof...(T)> PRINT_TUPLE(ostream &os, const tuple<T...> &t) {}
template<size_t num = 0, typename... T> enable_if_t<num <  sizeof...(T)> PRINT_TUPLE(ostream &os, const tuple<T...> &t) { os << get<num>(t); if (num + 1 < sizeof...(T)) os << ", "; PRINT_TUPLE<num + 1>(os, t); }
template<typename... T> ostream &operator<<(ostream &os, const tuple<T...> &t) { PRINT_TUPLE(os << '{', t); return os << '}'; }
template<class C, enable_if_t<!is_same<C, string>::value, decltype(declval<const C &>().begin(), nullptr)>> ostream& operator<<(ostream &os, const C &c) { os << '{'; for (auto it = begin(c); it != end(c); it++) { if (begin(c) != it) os << ", "; os << *it; } return os << '}'; }
template<typename T> ostream &operator<<(ostream &os, const stack<T> &j) { deque<T> d; for (auto c = j; !c.empty(); c.pop()) d.push_front(c.top());  return os << d; }
template<typename T> ostream &operator<<(ostream &os, const queue<T> &j) { deque<T> d; for (auto c = j; !c.empty(); c.pop()) d.push_back(c.front()); return os << d; }
template<typename T, typename C, typename Cmp> ostream &operator<<(ostream &os, const priority_queue<T, C, Cmp> &j) { deque<T> d; for (auto c = j; !c.empty(); c.pop()) d.push_front(c.top());  return os << d; }
// OUTPUT FUNCTION
template<typename T> int PV(T &v) { int sz = v.size(); for (int i = 0; i < sz; ++i) cout << v[i] << " \n"[i == sz - 1]; return 0; }
inline int print() { cout << endl; return 0; }
template<typename Head> int print(Head&& head){ cout << head; return print(); }
template<typename Head, typename... Tail> int print(Head&& head, Tail&&... tail) { cout << head << " "; return print(forward<Tail>(tail)...); }
#ifdef LOCAL
inline void dump() { cerr << endl; }
template<typename Head> void dump(Head&& head) { cerr << head; dump(); }
template<typename Head, typename... Tail> void dump(Head&& head, Tail&&... tail) { cerr << head << ", "; dump(forward<Tail>(tail)...); }
#define debug(...) do {cerr << __LINE__ << ":\t" << #__VA_ARGS__ << " = "; dump(__VA_ARGS__); } while (false)
#else
#define dump(...)
#define debug(...)
#endif
/* OTHER */
#define fi              first
#define se              second
#define MP              make_pair
#define MT              make_tuple
#define tmax(x, y, z)   max((x), max((y), (z)))
#define tmin(x, y, z)   min((x), min((y), (z)))
template<typename T, typename A, typename B> inline bool between(T x, A a, B b) { return ((a <= x) && (x < b)); }
template<typename A, typename B> inline bool chmax(A &a, const B &b) { if (a < b) { a = b; return true; } return false; }
template<typename A, typename B> inline bool chmin(A &a, const B &b) { if (a > b) { a = b; return true; } return false; }
inline ll gcd(ll a, ll b) { return b ? gcd(b, a % b) : a; }
inline ll lcm(ll a, ll b) { return a / gcd(a, b) * b; }
inline ll POW(ll a, ll b)                    { ll r = 1; do { if (b & 1)  r *= a;        a *= a; }       while (b >>= 1); return r; }
inline ll MOP(ll a, ll b, const ll &m = MOD) { ll r = 1; do { if (b & 1) (r *= a) %= m; (a *= a) %= m; } while (b >>= 1); return r; }
struct abracadabra {
	abracadabra() {
		cin.tie(nullptr); ios::sync_with_stdio(false);
		cout << fixed << setprecision(20);
		cerr << fixed << setprecision(5);
	};
} ABRACADABRA;

#pragma endregion
#pragma region compression
template<typename T> vector<T> compress(vector<T> ord, map<T, int> &rev) {
	// template<typename T> vector<T> compress(vector<T> ord) { map<T, int> rev;
	vector< T > com = ord;
	sort(com.begin(), com.end());
	com.erase(unique(com.begin(), com.end()), com.end());
	for (int i = 0; i < com.size(); ++i) rev[com[i]] = i;
	vector< T > ret; for (auto& e : ord) ret.emplace_back(rev[e]);
	return ret;
}

/*
   ・座標圧縮
   > O(NlogN)
   [備考] 各数字の対応関係が欲しいときは, 引数にmapを入れてコメントアウトを外す.
   [使用例]
   1. 引数にmapを入れない場合
   vector<long long> com = compress(v);
   2. 引数にmapを入れる場合
   map<long long, int> rev;
   vector<long long> com = compress(v, rev);
 */
#pragma endregion

ll res;
vector<vector<int>> graph;
vector<bool> visited;
vector<int> cx, cy;

const int dx[] = { 1, 0, -1,  0,  1, -1, -1, 1, 0 };
const int dy[] = { 0, 1,  0, -1, -1, -1,  1, 1, 0 };
// D, R, U, L
bool cango[3010 * 3010 + 10][4];
enum {D, R, U, L};

int x_sz, y_sz;

int f(int x, int y) {
	return x * y_sz + y;
}

map<ll, ll> revrev_x, revrev_y;
ll area(int x, int y) {
	ll ret = ll(cx[x + 1] - cx[x]) * (cy[y + 1] - cy[y]);
	// print(x, y, ret);
	return ret;
}

void dfs(int x, int y) {
	// print(x, y);
	if (x == 0 or y == 0 or x == x_sz - 1 or y == y_sz - 1) {
		print("INF");
		exit(0);
	}
	int idx = f(x, y);
	if (visited[idx]) return;
	visited[idx] = true;
	res += area(x, y);
	REP(k, 4) {
		if (not cango[idx][k]) continue;
		int nx = x + dx[k];
		int ny = y + dy[k];
		if (visited[f(nx, ny)]) continue;
		dfs(nx, ny);
	}
}

signed main() {

	SS(int, N, M);
	REP(i, 3010 * 3010 + 10) REP(j, 4) cango[i][j] = true;

	vector<int> v_x, v_y;

	// 番兵
	v_x.emplace_back(0);
	v_x.emplace_back(-INF);
	v_x.emplace_back( INF);
	v_y.emplace_back(0);
	v_y.emplace_back(-INF);
	v_y.emplace_back( INF);

	vector<tuple<int, int, int>> ABC;
	vector<tuple<int, int, int>> DEF;


	REP(i, N) {
		SS(int, A, B, C);
		v_x.emplace_back(A);
		v_x.emplace_back(B);
		v_y.emplace_back(C);
		ABC.emplace_back(A, B, C);
	}

	REP(i, N) {
		SS(int, D, E, F);
		v_x.emplace_back(D);
		v_y.emplace_back(E);
		v_y.emplace_back(F);
		DEF.emplace_back(D, E, F);
	}

	map<int, int> rev_x, rev_y;
	compress(v_x, rev_x);
	compress(v_y, rev_y);

	cx = v_x;   UNIQUE(cx);
	cy = v_y;   UNIQUE(cy);

	x_sz = rev_x.size();
	y_sz = rev_y.size();
	graph.resize(x_sz * y_sz);
	visited.resize(x_sz * y_sz);

	// debug(rev_x);
	// debug(rev_y);

	for (auto& [A, B, C]: ABC) {
		int ra = rev_x[A];
		int rb = rev_x[B];
		int  y = rev_y[C];
		for (int x = ra; x < rb; ++x) {
			cango[f(x, y - 1)][R] = false;
			cango[f(x, y    )][L] = false;
		}
	}

	for (auto& [DD, E, F]: DEF) {
		int  x = rev_x[DD];
		int re = rev_y[E];
		int rf = rev_y[F];
		for (int y = re; y < rf; ++y) {
			cango[f(x - 1, y)][D] = false;
			cango[f(x    , y)][U] = false;
		}
	}

	int zx = rev_x[0];
	int zy = rev_y[0];
	dfs(zx, zy);
	dfs(zx-1, zy);
	dfs(zx, zy-1);
	dfs(zx-1, zy-1);
	print(res);

}



Compiler output:
a.cc:24:81: warning: missing terminating " character
   24 | const int MOD = 1e9 + 7;    const int MODD = 998244353; const string alphabet = "abcdefghi
      |                                                                                 ^
a.cc:24:81: error: missing terminating " character
   24 | const int MOD = 1e9 + 7;    const int MODD = 998244353; const string alphabet = "abcdefghi
      |                                                                                 ^~~~~~~~~~
a.cc:25:12: warning: missing terminating " character
   25 | pqrstuvwxyz";
      |            ^
a.cc:25:12: error: missing terminating " character
   25 | pqrstuvwxyz";
      |            ^~
a.cc:25:1: error: 'pqrstuvwxyz' was not declared in this scope
   25 | pqrstuvwxyz";
      | ^~~~~~~~~~~