제출 #441257

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
441257		cheetose	Meetings 2 (JOI21_meetings2)	C++17	20 / 100	4062 ms	26412 KiB

meetings2

#include <bits/stdc++.h>
#define mp make_pair
#define pb push_back
#define X first
#define Y second
#define y0 y12
#define y1 y22
#define INF 1987654321
#define PI 3.141592653589793238462643383279502884
#define fup(i,a,b,c) for(int (i)=(a);(i)<=(b);(i)+=(c))
#define fdn(i,a,b,c) for(int (i)=(a);(i)>=(b);(i)-=(c))
#define MEM0(a) memset((a),0,sizeof(a))
#define MEM_1(a) memset((a),-1,sizeof(a))
#define ALL(a) a.begin(),a.end()
#define COMPRESS(a) sort(ALL(a));a.resize(unique(ALL(a))-a.begin())
#define SYNC ios_base::sync_with_stdio(false);cin.tie(0)
using namespace std;
typedef long long ll;
typedef long double ld;
typedef double db;
typedef unsigned int uint;
typedef unsigned long long ull;
typedef pair<int, int> Pi;
typedef pair<ll, ll> Pll;
typedef pair<db, db> Pd;
typedef vector<int> Vi;
typedef vector<ll> Vll;
typedef vector<ld> Vd;
typedef vector<Pi> VPi;
typedef vector<Pll> VPll;
typedef vector<Pd> VPd;
typedef tuple<int, int, int> iii;
typedef tuple<int, int, int, int> iiii;
typedef tuple<ll, ll, ll> LLL;
typedef vector<iii> Viii;
typedef vector<LLL> VLLL;
typedef complex<double> base;
const int MOD = 1000000007;
ll POW(ll a, ll b, ll MMM = MOD) { ll ret = 1; for (; b; b >>= 1, a = (a*a) % MMM)if (b & 1)ret = (ret*a) % MMM; return ret; }
int dx[] = { 0,1,0,-1,1,1,-1,-1 }, dy[] = { 1,0,-1,0,1,-1,1,-1 };
int ddx[] = { -1,-2,1,-2,2,-1,2,1 }, ddy[] = { -2,-1,-2,1,-1,2,1,2 };

Vi v[200001];
Vi vv[200001];
int dist[200001];
int bfs(int N){
	MEM_1(dist);
	queue<int> q;
	q.push(N);
	dist[N]=0;
	int last;
	while(!q.empty()){
		int x=q.front();
		q.pop();
		last=x;
		for(int y:vv[x]){
			if(dist[y]==-1){
				dist[y]=dist[x]+1;
				q.push(y);
			}
		}
	}
	return last;
}
int get_dia(int N){
	int t=bfs(N);
	t=bfs(t);
	return dist[t];
}
int cnt[200001];
void dfs(int N,int p=-1){
	cnt[N]=1;
	for(int next:v[N]){
		if(next==p)continue;
		dfs(next,N);
		cnt[N]+=cnt[next];
	}
}
int cc,n;
void dfs2(int N,int k,int p=-1){
	for(int next:v[N]){
		if(next==p)continue;
		if(cnt[next]>=k && n-cnt[next]>=k){
			cc=N;
			vv[N].pb(next);
			vv[next].pb(N);
		}
		dfs2(next,k,N);
	}
}
int main(){
	scanf("%d",&n);
	fup(i,1,n-1,1){
		int x,y;
		scanf("%d%d",&x,&y);
		v[x].pb(y);
		v[y].pb(x);
	}
	dfs(1);
	fup(i,1,n,1){
		if(i&1)puts("1");
		else{
			fup(ii,1,n,1)vv[ii].clear();
			dfs2(1,i/2);
			printf("%d\n",get_dia(cc)+1);
		}
	}
}

컴파일 시 표준 에러 (stderr) 메시지

meetings2.cpp: In function 'int main()':
meetings2.cpp:10:30: warning: unnecessary parentheses in declaration of 'i' [-Wparentheses]
   10 | #define fup(i,a,b,c) for(int (i)=(a);(i)<=(b);(i)+=(c))
      |                              ^
meetings2.cpp:93:2: note: in expansion of macro 'fup'
   93 |  fup(i,1,n-1,1){
      |  ^~~
meetings2.cpp:10:30: warning: unnecessary parentheses in declaration of 'i' [-Wparentheses]
   10 | #define fup(i,a,b,c) for(int (i)=(a);(i)<=(b);(i)+=(c))
      |                              ^
meetings2.cpp:100:2: note: in expansion of macro 'fup'
  100 |  fup(i,1,n,1){
      |  ^~~
meetings2.cpp:10:30: warning: unnecessary parentheses in declaration of 'ii' [-Wparentheses]
   10 | #define fup(i,a,b,c) for(int (i)=(a);(i)<=(b);(i)+=(c))
      |                              ^
meetings2.cpp:103:4: note: in expansion of macro 'fup'
  103 |    fup(ii,1,n,1)vv[ii].clear();
      |    ^~~
meetings2.cpp:92:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   92 |  scanf("%d",&n);
      |  ~~~~~^~~~~~~~~
meetings2.cpp:95:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   95 |   scanf("%d%d",&x,&y);
      |   ~~~~~^~~~~~~~~~~~~~
meetings2.cpp: In function 'int bfs(int)':
meetings2.cpp:63:9: warning: 'last' may be used uninitialized in this function [-Wmaybe-uninitialized]
   63 |  return last;
      |         ^~~~

• Subtask 1: 4 / 4
• Subtask 2: 16 / 16
• Subtask 3: 0 / 80