Submission #896307

#	Time	Username	Problem	Language	Result	Execution time	Memory
896307		arashMLG	Tug of War (BOI15_tug)	C++17	100 / 100	1557 ms	10844 KiB

tug

#include<bits/stdc++.h>
#ifdef LOCAL
#include "Essentials/algo/debug.h"
#else
#define debug(...) 69
#endif
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
using namespace std;

typedef long long     ll;
typedef pair<int,int> pii;
typedef pair<ll,ll>   pll;

const int M = 3e4 + 23;
const int N =M*2;
const int LOG = 20;
const int ZERO = N*LOG/2;
const ll inf = 1e18;

#define F           first
#define S           second
#define pb          push_back
#define kill(x)     cout<<x<<endl, exit(0);
#define all(x)      x.begin(),x.end()
#define sz(x)       (int)x.size()
#define lc          (v << 1)
#define rc          ((v<<1) |1)

int n,k;
int w[N];
set<pii> G[N];
vector<int> vals;
bitset<N*LOG> dp;
int sum;

void dfs(int v,int sex = 1) {
	if(sz(G[v])) {
		pii u = *G[v].begin();
		G[v].clear();
		G[u.F].erase({v,u.S});
		sum += sex * w[u.S];
		dfs(u.F,-sex);
	}	
}

queue<int> Q;

int32_t main() {
    cin.tie(nullptr)->sync_with_stdio(false);
	cin>>n>>k;
	for(int i=0; i< 2*n ; i ++) {
		int l,r; cin>>l>>r>>w[i]; l--,r--;
		r += n;
		G[l].insert({r,i});
		G[r].insert({l,i});
	}
	for(int i = 0; i<2*n ; i ++) {
		if(!sz(G[i])) kill("NO");
		if(sz(G[i]) == 1) {
			Q.push(i);
		}
	}
	int begsum = 0;
	while(sz(Q)) {
		int v = Q.front(); Q.pop();
		pii u = *G[v].begin();
		G[v].clear();
		G[u.F].erase({v,u.S});
		if(v < n) begsum += w[u.S];
		else begsum -= w[u.S];
		if(sz(G[u.F]) == 1) Q.push(u.F);
	}
	for(int i = 0; i < 2*n; i ++) if(sz(G[i])) {
		sum = 0; dfs(i); vals.pb(abs(sum));
	}
	dp[ZERO+begsum] = 1;
	debug(vals);
	for(int val : vals) {
		dp = (dp << val) | (dp >> val);
	}
	for(int i = 0 ; i < N*LOG; i ++) if(dp[i] && abs(ZERO - i) <= k) kill("YES");
	kill("NO");
	return 0;
}

// Jumpsuit, Jumpsuit cover me!
// Jumpsuit, Jumpsuit cover me!

Compilation message (stderr)

tug.cpp: In function 'int32_t main()':
tug.cpp:5:20: warning: statement has no effect [-Wunused-value]
    5 | #define debug(...) 69
      |                    ^~
tug.cpp:79:2: note: in expansion of macro 'debug'
   79 |  debug(vals);
      |  ^~~~~

• Subtask 1: 18 / 18
• Subtask 2: 30 / 30
• Subtask 3: 23 / 23
• Subtask 4: 29 / 29