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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#622394#6107. One PathcjxWA 30ms4100kbC++203.8kb2024-10-08 21:23:302024-10-08 21:23:31

Judging History

你现在查看的是最新测评结果

  • [2024-10-08 21:23:31]
  • 评测
  • 测评结果:WA
  • 用时:30ms
  • 内存:4100kb
  • [2024-10-08 21:23:30]
  • 提交

answer

#include<bits/stdc++.h>
#define ll long long
#define pii pair<int,int>
#define fi first
#define se second
using namespace std;
long long read(){
	long long x=0,f=1;char ch=getchar();
	while(!isdigit(ch))
	{if(ch=='-') f=-1;ch=getchar();}
	while(isdigit(ch)){x=x*10+ch-48;ch=getchar();}
	return x*f;
}
void write(long long x){
    if(x<0) putchar('-'),x=-x;
    if(x>9) write(x/10);
    putchar(x%10+'0');
}
const int N=2010;
int n,k;
int head[N],ver[N<<1],nxt[N<<1],tot;
ll edge[N<<1],dep[N];
set<pair<pii,ll> >sedge;
void add(int x,int y,ll z){
	ver[++tot]=y,edge[tot]=z,nxt[tot]=head[x],head[x]=tot;
}
int dfn[N],num,eul[N<<1],red[N],nume,rnk[N],ted[N];
int mu,mv,mx,my;
ll mw,me;
struct ST{
    int f[N<<1][14];
    int Log[N<<1];
    int op(int x,int y){
        return dep[x]<dep[y]?x:y;
    }
    void init(int n,int *a){
        Log[0]=-1;
        for(int i=1;i<=n;i++)f[i][0]=a[i],Log[i]=Log[i>>1]+1;
        for(int i=1;i<14;i++)
            for(int j=1;j+(1<<i)-1<=n;j++)
                f[j][i]=op(f[j][i-1],f[j+(1<<(i-1))][i-1]);
    }
    int ask(int l,int r){
        int k=Log[r-l+1];
        return op(f[l][k],f[r-(1<<k)+1][k]);
    }
}st;
void dfs1(int x,int fa){
    if(x==1)dep[x]=0;
    //printf("dep[%d]=%lld\n",x,dep[x]);
    rnk[dfn[x]=++num]=x;red[eul[x]=++nume]=x;
    for(int i=head[x];i;i=nxt[i]){
        int y=ver[i];
        if(y==fa)continue;
        dep[y]=dep[x]+edge[i];
        dfs1(y,x);
        red[++nume]=x;
    }
}
ll dist(int x,int y){
    return dep[x]+dep[y]-(dep[st.ask(min(eul[x],eul[y]),max(eul[x],eul[y]))]<<1);
}
struct Diam{
    int x,y;
    ll z;
    Diam(int xx=0,int yy=0){
        x=xx,y=yy;
        if(x)z=dist(x,y);else z=-1;
    }
    bool operator <(const Diam p)const{
        return z<p.z;
    }
}f[N];
Diam operator +(const Diam p,const Diam q){
    return max(max(p,q),max(max(Diam(p.x,q.x),Diam(p.x,q.y)),max(Diam(p.y,q.x),Diam(p.y,q.y))));
}
void dfs2(int x,int fa){
    f[x]=Diam(x,x);
    for(int i=head[x];i;i=nxt[i]){
        int y=ver[i];
        if(y==fa)continue;
        dfs2(y,x);
        f[x]=f[x]+f[y];
    }
    //printf("f[%d]=(%d,%d) %lld\n",x,f[x].x,f[x].y,f[x].z);
}
void init(){
	memset(head,0,sizeof(head));
	tot=num=nume=0;
	for(auto u:sedge){
		add(u.fi.fi,u.fi.se,u.se);add(u.fi.se,u.fi.fi,u.se);
	}
    dfs1(1,0);
    st.init(nume,red);
    dfs2(1,0);
    mu=mv=mx=my=me=0;mw=-1;
}
void dfs3(int x,int fa){
    vector<int>son;
    vector<ll>val;
    vector<Diam>pre,suf;
    son.clear();pre.clear();suf.clear();
    for(int i=head[x];i;i=nxt[i]){
        int y=ver[i];
        son.push_back(y);
        val.push_back(edge[i]);
        pre.push_back(f[y]);
        suf.push_back(f[y]);
    }
    for(int i=1;i<son.size();i++){
        pre[i]=pre[i-1]+pre[i];
    }
    for(int i=son.size()-2;i>=0;i--)
        suf[i]=suf[i+1]+suf[i];
    Diam now,e;
    for(int i=0;i<son.size();i++){
        int y=son[i];
        if(y==fa)continue;
        now=Diam(x,x);
        if(i>0)now=now+pre[i-1];
        if(i<son.size()-1)now=now+suf[i+1];
        f[x]=now;e=f[y];
        ll w=f[x].z+f[y].z+val[i];
        if(w>mw){
            mw=w;mu=x;mv=y;me=val[i];mx=f[x].x;my=f[y].y;
        }
        f[y]=f[y]+now;
        dfs3(y,x);
        f[y]=e;
    }
}
int main(){
	//freopen(".in","r",stdin);
	//freopen(".out","w",stdout);
	n=read();k=read();
	for(int i=1;i<n;i++){
		pair<pii,ll> u;
		u.fi.fi=read();u.fi.se=read();u.se=read();
		sedge.insert(u);
	}
    init();
    write(f[1].z);putchar(' ');
    while(k--){
        dfs3(1,0);
        write(mw);putchar(' ');
        if(mu>mv)swap(mu,mv);
        if(mx>my)swap(mx,my);
        sedge.erase(make_pair(make_pair(mu,mv),me));
        sedge.insert(make_pair(make_pair(mx,my),me));
        init();
    }
    puts("");
	return 0;
}

Details

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Test #1:

score: 100
Accepted
time: 0ms
memory: 3656kb

input:

5 1
1 3 2
4 5 4
3 4 3
2 3 7

output:

14 16 

result:

ok 2 number(s): "14 16"

Test #2:

score: 0
Accepted
time: 0ms
memory: 3624kb

input:

7 2
1 2 4
2 3 6
2 4 2
4 5 5
2 6 1
4 7 3

output:

13 20 21 

result:

ok 3 number(s): "13 20 21"

Test #3:

score: 0
Accepted
time: 30ms
memory: 3900kb

input:

50 2000
3 34 1
37 39 58720256
17 24 14680064
28 39 1
25 38 1
21 29 1
3 30 1
26 36 1
5 48 14336
4 22 1
26 41 1
41 44 1
5 14 1
23 25 28672
40 41 224
27 39 1
4 20 7340032
7 47 939524096
11 46 114688
30 49 3584
34 44 1
7 35 1
10 29 1
27 33 29360128
16 36 56
8 28 1
13 38 57344
34 45 896
15 35 469762048
1...

output:

1409286145 1761607683 1849688069 1871708167 1877213193 1878589451 1878933517 1879019535 1879041041 1879046419 1879047765 1879048103 1879048160 1879048160 1879048160 1879048160 1879048160 1879048160 1879048160 1879048160 1879048160 1879048160 1879048160 1879048160 1879048160 1879048160 1879048160 187...

result:

ok 2001 numbers

Test #4:

score: 0
Accepted
time: 0ms
memory: 3680kb

input:

10 5
1 4 10
3 7 138
1 9 162
4 10 113
4 6 12
5 6 171
2 10 31
7 8 12
7 10 132

output:

566 769 781 781 781 781 

result:

ok 6 numbers

Test #5:

score: 0
Accepted
time: 0ms
memory: 3904kb

input:

2 0
1 2 340241821

output:

340241821 

result:

ok 1 number(s): "340241821"

Test #6:

score: -100
Wrong Answer
time: 1ms
memory: 4100kb

input:

2000 0
450 1620 747893383
103 1602 466748018
746 1996 468886757
430 764 455748265
1201 1275 111041658
244 802 715844971
611 899 125646661
1105 1633 478144612
180 573 823370712
161 1018 67225549
1512 1915 538711443
829 1871 761057722
1297 1499 576790037
1492 1832 983172784
1486 1902 78076400
1206 121...

output:

120545921643 

result:

wrong answer 1st numbers differ - expected: '83343544566', found: '120545921643'