Submission #406122

#	Time	Username	Problem	Language	Result	Execution time	Memory
406122		codebuster_10	Tug of War (BOI15_tug)	C++17	18 / 100	12 ms	4860 KiB

tug

#include <bits/stdc++.h>

using namespace std ;

#define int int64_t //be careful about this 
#define endl "\n"
#define f(i,a,b) for(int i=int(a);i<int(b);++i)

#define pr pair
#define ar array
#define fr first
#define sc second
#define vt vector
#define pb push_back
#define eb emplace_back
#define LB lower_bound  
#define UB upper_bound
#define PQ priority_queue

#define sz(x) ((int)(x).size())
#define all(a) (a).begin(),(a).end()
#define allr(a) (a).rbegin(),(a).rend()
#define mem0(a) memset(a, 0, sizeof(a))
#define mem1(a) memset(a, -1, sizeof(a))

template<class A> void rd(vt<A>& v);
template<class T> void rd(T& x){ cin >> x; }
template<class H, class... T> void rd(H& h, T&... t) { rd(h) ; rd(t...) ;}
template<class A> void rd(vt<A>& x) { for(auto& a : x) rd(a) ;}

template<class T> bool ckmin(T& a, const T& b) { return b < a ? a = b, 1 : 0; }
template<class T> bool ckmax(T& a, const T& b) { return a < b ? a = b, 1 : 0; }

template<typename T>
void __p(T a) {
  cout<<a; 
}
template<typename T, typename F>
void __p(pair<T, F> a) {
  cout<<"{";
  __p(a.first);
  cout<<",";
  __p(a.second);
  cout<<"}\n"; 
}
template<typename T>
void __p(std::vector<T> a) {
  cout<<"{";
  for(auto it=a.begin(); it<a.end(); it++)
    __p(*it),cout<<",}\n"[it+1==a.end()]; 
}
template<typename T, typename ...Arg>
void __p(T a1, Arg ...a) {
  __p(a1);
  __p(a...);
}
template<typename Arg1>
void __f(const char *name, Arg1 &&arg1) {
  cout<<name<<" : ";
  __p(arg1);
  cout<<endl;
}
template<typename Arg1, typename ... Args>
void __f(const char *names, Arg1 &&arg1, Args &&... args) {
  int bracket=0,i=0;
  for(;; i++)
    if(names[i]==','&&bracket==0)
      break;
    else if(names[i]=='(')
      bracket++;
    else if(names[i]==')')
      bracket--;
  const char *comma=names+i;
  cout.write(names,comma-names)<<" : ";
  __p(arg1);
  cout<<" | ";
  __f(comma+1,args...);
}

void setIO(string s = "") {
  ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0); 
  cin.exceptions(cin.failbit); 
	cout.precision(15);	cout << fixed;
  #ifdef ONLINE_JUDGE
  if(sz(s)){
  	freopen((s+".in").c_str(),"r",stdin);
  	freopen((s+".out").c_str(),"w",stdout);
  }
  #define __f(...) 0
  #endif
}
void err(){
	cout << "NO"; exit(0);
}
const int MX = 20 * 60000 + 1;
signed main(){
  setIO() ;
	int n,k; rd(n,k);
	vt<tuple<int,int,int>> g[2*n]; // {node,weight,id of edge}
	f(id,0,2*n){
		int l,r,s; rd(l,r,s);
		--l,--r;
		g[l].eb(r+n,s,id);
		g[r+n].eb(l,s,id);
	}
	vt<bool> vis(2*n,false), vis_node(n,false);
	vt<int> W;
	f(k,0,n) if(!vis_node[k]){
		int x = 0, edges = 0, nodes = 0;
		function<void(int)> dfs=[&](int i){
			++nodes;
			vis_node[i] = true;
			for(auto [j,w,id] : g[i]) if(!vis[id]){
				vis[id] = true;
				++edges;
				if(j<n) x += w;
				else		x -= w;
				if(!vis_node[j]) dfs(j);
			}
		};
		dfs(k);
		if(nodes != edges) err();
		W.pb(abs(x));
	}
	int sum = accumulate(all(W),0);
	bitset<MX> is;
	is[0] = true;
	for(auto i : W) is |= (is << i);
	f(i,0,MX){
		if(abs(sum - 2*i) <= k && is[i]){
			cout << "YES"; exit(0);
		}
	}
	err();
	
}

• Subtask 1: 18 / 18
• Subtask 2: 0 / 30
• Subtask 3: 0 / 23
• Subtask 4: 0 / 29