#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
using db = double;
using str = string;
using pi = pair<int, int>;
using pl = pair<ll, ll>;
using pd = pair<db, db>;
using vi = vector<int>;
using vb = vector<bool>;
using vl = vector<ll>;
using vd = vector<db>;
using vs = vector<str>;
using vpi = vector<pi>;
using vpl = vector<pl>;
using vpd = vector<pd>;
#define mp make_pair
#define f first
#define s second
#define sz(x) (int)(x).size()
#define bg(x) begin(x)
#define all(x) bg(x), end(x)
#define sor(x) sort(all(x))
#define ft front()
#define bk back()
#define pb push_back
#define pf push_front
#define lb lower_bound
#define ub upper_bound
#define FOR(i,a,b) for (int i = (a); i < (b); ++i)
#define F0R(i,a) FOR(i,0,a)
#define ROF(i,a,b) for (int i = (b)-1; i >= (a); --i)
#define R0F(i,a) ROF(i,0,a)
#define EACH(a,x) for (auto& a: x)
const int MOD = 1e9 + 7;
const int MX = 3e4 + 10;
const ll INF = 1e18;
int N, K; multiset<pi> adj[2 * MX]; bool vis[2 * MX]; vi todo;
void DFS(int X) {
vis[X] = true; pi E = *adj[X].bg();
tot += E.s; if (!vis[E.f]) { adj[X].clear(); adj[E.f].erase(adj[E.f].find({X, -E.s})); DFS(E.f); }
}
int main() {
ios_base::sync_with_stdio(false); cin.tie(0);
cin >> N >> K; F0R(i, 2 * N) {
int A, B, S; cin >> A >> B >> S;
adj[A].insert({N + B, S}), adj[N + B].insert({A, -S});
}
queue<int> Q; FOR(i, 1, 2 * N + 1) {
if (sz(adj[i]) == 0) { cout << "NO"; return 0; }
if (sz(adj[i]) == 1) Q.push(i);
}
while (!Q.empty()) {
int cur = Q.front(); Q.pop(); if (sz(adj[cur]) == 0) { cout << "NO"; return 0; }
pi E = *adj[cur].bg(); tot += E.s; adj[cur].clear(); adj[E.f].erase(adj[E.f].find({cur, -E.s}));
if (sz(adj[E.f]) == 1) Q.push(E.f);
}
if (tot) todo.pb(abs(tot)); FOR(i, 1, 2 * N + 1) if (!vis[i] && sz(adj[i])) {
tot = 0; adj[i].erase(adj[i].bg()); DFS(i); if (tot) todo.pb(abs(tot));
}
bitset<40 * MX> DP; DP[20 * MX] = 1;EACH(C, todo) DP = (DP << C) | (DP >> C);
FOR(i, 20 * MX - K, 20 * MX + K + 1) if (DP[i]) { cout << "YES"; return 0; } cout << "NO";
}
Compilation message
tug.cpp: In function 'void DFS(int)':
tug.cpp:54:5: error: 'tot' was not declared in this scope
54 | tot += E.s; if (!vis[E.f]) { adj[X].clear(); adj[E.f].erase(adj[E.f].find({X, -E.s})); DFS(E.f); }
| ^~~
tug.cpp: In function 'int main()':
tug.cpp:73:32: error: 'tot' was not declared in this scope
73 | pi E = *adj[cur].bg(); tot += E.s; adj[cur].clear(); adj[E.f].erase(adj[E.f].find({cur, -E.s}));
| ^~~
tug.cpp:77:9: error: 'tot' was not declared in this scope
77 | if (tot) todo.pb(abs(tot)); FOR(i, 1, 2 * N + 1) if (!vis[i] && sz(adj[i])) {
| ^~~
tug.cpp:78:9: error: 'tot' was not declared in this scope
78 | tot = 0; adj[i].erase(adj[i].bg()); DFS(i); if (tot) todo.pb(abs(tot));
| ^~~
tug.cpp:39:20: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
39 | #define FOR(i,a,b) for (int i = (a); i < (b); ++i)
| ^~~
tug.cpp:82:5: note: in expansion of macro 'FOR'
82 | FOR(i, 20 * MX - K, 20 * MX + K + 1) if (DP[i]) { cout << "YES"; return 0; } cout << "NO";
| ^~~
tug.cpp:82:82: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
82 | FOR(i, 20 * MX - K, 20 * MX + K + 1) if (DP[i]) { cout << "YES"; return 0; } cout << "NO";
| ^~~~
