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ID题目提交者结果用时内存语言文件大小提交时间测评时间
#40796#2065. Cyclic DistancelycheesWA 56ms14112kbC++2.8kb2022-07-26 20:53:272022-07-26 20:53:30

Judging History

你现在查看的是最新测评结果

  • [2023-08-10 23:21:45]
  • System Update: QOJ starts to keep a history of the judgings of all the submissions.
  • [2022-07-26 20:53:30]
  • 评测
  • 测评结果:WA
  • 用时:56ms
  • 内存:14112kb
  • [2022-07-26 20:53:27]
  • 提交

answer

#include <bits/stdc++.h>
using namespace std;
#define rep(i,a,n) for (int i=a;i<n;i++)
#define per(i,a,n) for (int i=n-1;i>=a;i--)
#define pb push_back
#define mp make_pair
#define all(x) (x).begin(),(x).end()
#define fi first
#define se second
#define SZ(x) ((int)(x).size())
typedef vector<int> VI;
typedef long long ll;
typedef pair<int,int> PII;
typedef double db;
mt19937 mrand(random_device{}());
const ll mod=1000000007;
int rnd(int x) { return mrand() % x;}
ll powmod(ll a,ll b) {ll res=1;a%=mod; assert(b>=0); for(;b;b>>=1){if(b&1)res=res*a%mod;a=a*a%mod;}return res;}
ll gcd(ll a,ll b) { return b?gcd(b,a%b):a;}
// head

const int N=201000;
int n,u,v,w,rt,T,_,mt[N],cnt[N],k,pv[N],mark[N];
ll ans;
vector<PII> e[N];
vector<array<ll,3>> dis;

void dfs(int u,int f,int br,ll d) {
	dis.pb({d,br,u});
	for (auto p:e[u]) {
		int v=p.fi;
		if (v==f) continue;
		dfs(v,u,br==rt?v:br,d+p.se);
	}
}

void solve(int x) {
	rt=x;
	dis.clear();
	dfs(rt,0,rt,0);
	sort(all(dis)); reverse(all(dis));
	T++;
	ll tmp=0;
	int pt=0;
	for (auto x:dis) {
		if (mt[x[1]]!=T) mt[x[1]]=T,cnt[x[1]]=0;
		if (pt<k&&cnt[x[1]]<k/2) {
            pt++; cnt[x[1]]++; tmp+=x[0]; mark[x[2]]=T;
            if (pt == k) {
               if (tmp>ans) {
                    ans=tmp;
                    rep(i,1,n+1) pv[i]=(mark[i]==T);
                }
                return;
            }
		 }
	}
}

int q[N],f[N],vis[N],sz[N],ms[N];
int find(int u) {
	int t=1;q[0]=u;f[u]=-1;
	rep(i,0,t) {
		u=q[i];
		rep(j,0,e[u].size()) {
			int v=e[u][j].fi;
			if (!vis[v]&&v!=f[u]) f[q[t++]=v]=u;
		}
		ms[q[i]]=0;
		sz[q[i]]=1;
	}
	for (int i=t-1;i>=0;i--) {
		ms[q[i]]=max(ms[q[i]],t-sz[q[i]]);
		if (ms[q[i]]*2<=t) return q[i];
		sz[f[q[i]]]+=sz[q[i]];
		ms[f[q[i]]]=max(ms[f[q[i]]],sz[q[i]]);
	}
	return 0;
}

void gao(int u) {
	u=find(u);
	solve(u);
	T++;
	int maj=-1;
	rep(i,0,k) {
		auto x=dis[i];
	//	printf("dd %lld %lld %lld\n",x[0],x[1],x[2]);
		if (mt[x[1]]!=T) mt[x[1]]=T,cnt[x[1]]=0;
		cnt[x[1]]++;
		if (cnt[x[1]]>k/2) maj=x[1];
	}
	vis[u]=1;
	//fprintf(stderr,"%d %d\n",u,maj);
	if (maj!=-1&&!vis[maj]) gao(maj);
}

pair<ll,int> dfs(int u,int f) {
	int fv=pv[u];
	ll mdis=0;
	for (auto p:e[u]) {
		int v=p.fi;
		if (v==f) continue;
		auto z=dfs(v,u);
		if (z.se<k/2) z.fi+=p.se;
		fv+=z.se;
		mdis=max(mdis,z.fi);
	}
	if (pv[u]) mdis=-(1ll<<60);
	return mp(mdis,fv);
}

void solve() {
	scanf("%d%d",&n,&k);
	rep(i,1,n+1) e[i].clear(),vis[i]=0;
	ans=0;
	for (int i=1;i<n;i++) {
		scanf("%d%d%d",&u,&v,&w);
		e[u].pb(mp(v,w));
		e[v].pb(mp(u,w));
	}
	/*
	if (k%2==1) {
		--k;
		gao(1);
		ans+=dfs(rt,0).fi;
	} else */
	gao(1);
	printf("%lld\n",2*ans);
}

int main() {
	for (scanf("%d",&_);_;_--) solve();
}

詳細信息

Test #1:

score: 100
Accepted
time: 0ms
memory: 14112kb

input:

1
5 3
1 2 4
1 3 1
1 4 8
4 5 9

output:

44

result:

ok single line: '44'

Test #2:

score: 0
Accepted
time: 32ms
memory: 13952kb

input:

57206
3 2
1 2 574927
2 3 406566
2 2
1 2 308806
4 3
1 2 312588
2 3 500141
2 4 53602
3 3
1 2 797183
2 3 944061
5 3
1 2 624010
2 3 488613
3 4 734514
4 5 497493
5 4
1 2 540278
2 3 488655
2 4 228989
2 5 653896
2 2
1 2 569117
4 2
1 2 821764
2 3 499471
1 4 549060
2 2
1 2 991159
2 2
1 2 482941
5 4
1 2 30462...

output:

1962986
617612
1732662
3482488
4689260
3823636
1138234
3740590
1982318
965882
3418504
5026562
1623414
1885106
1952142
3050630
1691896
3102076
2380932
3076270
5697196
7258020
879020
2500212
3613854
1358950
1182198
2273662
2331560
1681964
8917452
2373066
3163042
3104226
3642898
3162310
5058442
3669186...

result:

ok 57206 lines

Test #3:

score: 0
Accepted
time: 56ms
memory: 11960kb

input:

57087
3 3
1 2 34132
1 3 188096
2 2
1 2 996527
2 2
1 2 475736
5 3
1 2 329834
2 3 339687
1 4 954113
4 5 224354
2 2
1 2 641444
2 2
1 2 114059
5 3
1 2 635722
1 3 552627
1 4 721758
3 5 396156
4 3
1 2 655099
2 3 963393
1 4 953969
5 2
1 2 369719
1 3 22087
1 4 531252
3 5 449025
4 3
1 2 788498
1 3 220292
1 4...

output:

444456
1993054
951472
3695976
1282888
228118
4612526
5144922
2004728
3309502
2626844
3053048
3939444
3790784
2617770
38866
3033250
5707738
511666
403846
1923106
3331606
3447180
2329518
5656124
33582
2283312
3454982
110590
3125394
4517486
4522330
2352316
3966810
3463746
5181112
3089346
1260326
466418...

result:

ok 57087 lines

Test #4:

score: -100
Wrong Answer
time: 47ms
memory: 14072kb

input:

33344
9 6
1 2 562996
1 3 312637
3 4 591016
1 5 811983
2 6 896220
3 7 854379
2 8 861166
1 9 672337
8 6
1 2 53530
1 3 712638
1 4 539356
1 5 179377
3 6 456495
2 7 730760
4 8 934379
3 3
1 2 87024
1 3 328551
3 3
1 2 664600
1 3 519786
5 4
1 2 374521
1 3 484148
2 4 501378
1 5 280691
10 3
1 2 676949
1 3 639...

output:

12876734
9717058
831150
2368772
4030518
7963678
2135868
739728
11584454
1670128
3432160
5573124
1293282
3608364
8574290
6242670
10860048
4726106
4903320
9713590
5160212
5958260
14418122
1913782
1393854
5129544
9369494
11601220
4751232
1623938
8259790
3591252
5112182
4761950
5284034
13000192
4895040
...

result:

wrong answer 19th lines differ - expected: '5661430', found: '4903320'