Submission #1030654

#	Time	Username	Problem	Language	Result	Execution time	Memory
1030654		vjudge1	Simurgh (IOI17_simurgh)	C++17	51 / 100	108 ms	2616 KiB

simurgh

#include<bits/stdc++.h>
using namespace std;
#define rep(i,n) for(int i=0; i<(n); i++)
#define rng(i,l,r) for(int i=(l); i<(r); i++)
#define all(x) x.begin(),x.end()
using ll=long long;
const int INF=INT_MAX>>1;
#include "simurgh.h"

struct UnionFind{
	int size;
	vector<int> uf;
	UnionFind(int sz):size(sz){
		uf.resize(sz,-1);
	}
	int leader(int x){
		if(uf[x]<0)return x;
		uf[x]=leader(uf[x]);
		return uf[x];
	}
	bool same(int x,int y){
		return leader(x)==leader(y);
	}
	bool merge(int x,int y){
		x=leader(x);
		y=leader(y);
		if(x==y)return false;
		if(-uf[x]>-uf[y])swap(x,y);
		uf[y]+=uf[x];
		uf[x]=y;
		return true;
	}
};
std::vector<int> find_roads(int n, std::vector<int> u, std::vector<int> v) {
	vector<int> tree;
	int m=u.size();
	UnionFind uni(n);
	rep(i,m){
		if(uni.merge(u[i],v[i]))tree.emplace_back(i);
	}
	vector<int> ans;
	int def=count_common_roads(tree);
	vector<int> mark(m+1,0);
	rep(i,n-1){
		UnionFind uni(n);
		int bef=tree[i];
		rep(j,n-1){
			if(i!=j)uni.merge(u[tree[j]],v[tree[j]]);
		}
		vector<pair<int,int>> num={{def,bef}};
		bool checked=false;
		rep(j,m){
			if(j==bef)continue;
			if(!uni.same(u[j],v[j])){
				if(mark[j]!=0){
					if(checked)continue;
					checked=true;
				}
				tree[i]=j;
				num.emplace_back(count_common_roads(tree),j);
				if(mark[j]==-1)num.emplace_back(num.back().first+1,m);
				tree[i]=bef;
			}
		}
		sort(all(num));
		for(auto &[v,j]:num){
			//cout<<v<<" "<<j<<endl;
			if(v==num.back().first)mark[j]=1;
			else mark[j]=-1;
		}
	}
	rep(i,m){
		if(mark[i]==1)ans.emplace_back(i);
	}
	return ans;
}

• Subtask 1: 13 / 13
• Subtask 2: 17 / 17
• Subtask 3: 21 / 21
• Subtask 4: 0 / 19
• Subtask 5: 0 / 30