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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
#419991#8716. 树yangyuchen17WA 1ms9692kbC++142.3kb2024-05-24 13:38:002024-05-24 13:38:00

Judging History

你现在查看的是最新测评结果

  • [2024-05-24 13:38:00]
  • 评测
  • 测评结果:WA
  • 用时:1ms
  • 内存:9692kb
  • [2024-05-24 13:38:00]
  • 提交

answer

#include<bits/stdc++.h>
using namespace std;
typedef long long LL;
const int N=2e5+5,M=2*N;

int n,m,q,b[N],deep[N],f[N][20];
int a[N],c[N];
int h[N],e[M],ne[M],idx;

void add(int u,int v){
    e[idx]=v,ne[idx]=h[u],h[u]=idx++;
}

bool vis[N];
void dfs1(int u){
    vis[u]=true;
    for(int i=h[u];~i;i=ne[i]){
        int v=e[i];
        if(vis[v]) continue;
        deep[v]=deep[u]+1;
        f[v][0]=u;
        for(int j=1;j<20;j++) f[v][j]=f[f[v][j-1]][j-1];
        dfs1(v);
    }
}

int main(){
    cin>>n>>m>>q;
    memset(h,-1,sizeof h);
    a[1]=c[n]=-1;
    int u,v,ans=2;
    for(int i=1;i<n;i++){
        cin>>u>>v;
        add(u,v),add(v,u);
    }
    dfs1(1);
    cin>>b[1];
    for(int i=2;i<=m;i++){
        cin>>b[i];
        int x=b[i],y=b[i-1],d=deep[b[i]]-deep[b[i-1]],cnt=0;
        if(d<0) d=-d,swap(x,y);
        a[i]=f[b[i]][0],c[i-1]=f[b[i-1]][0];
        if(d){
        	d--;
			while(d){
        		if(d&1) x=f[x][cnt];
        		d>>=1,cnt++;
			}
			if(f[x][0]==y){
				if(deep[b[i]]>deep[b[i-1]]) c[i-1]=x;
				else a[i]=x;
			}
		}
		if(a[i-1]==c[i-1]) ans++;
    }
    int i;
    while(q--){
        cin>>i>>u;
        b[i]=u;
        if(a[i]==c[i]) ans--;
        if(i!=n){
        	if(a[i+1]==c[i+1]) ans--;
        	int x=b[i+1],y=b[i],d=deep[x]-deep[y],cnt=0;
    	    if(d<0) d=-d,swap(x,y);
    	    a[i+1]=f[b[i+1]][0],c[i]=f[b[i]][0];
    	    if(d){
    	    	d--;
    	   		while(d){
    	    		if(d&1) x=f[x][cnt];
    	    		d>>=1,cnt++;
				}
				if(f[x][0]==y){
					if(deep[b[i+1]]>deep[b[i]]) c[i]=x;
					else a[i+1]=x;
				}
			}
			if(a[i+1]==c[i+1]) ans++;
		}
		if(i!=1){
			if(a[i-1]==c[i-1]) ans--;
			int x=b[i],y=b[i-1],d=deep[x]-deep[y],cnt=0;
    	    if(d<0) d=-d,swap(x,y);
    	    a[i]=f[b[i]][0],c[i-1]=f[b[i-1]][0];
    	    if(d){
    	 		d--;
    	 		while(d){
    	  	  	if(d&1) x=f[x][cnt];
    	    		d>>=1,cnt++;
				}
				if(f[x][0]==y){
					if(deep[b[i]]>deep[b[i-1]]) c[i-1]=x;
					else a[i]=x;
				}	
			}
			if(a[i-1]==c[i-1]) ans++;
		}
		if(a[i]==c[i]) ans++;
        cout<<ans<<endl;
        /*
        for(int i=1;i<=m;i++){
            cout<<b[i]<<":"<<a[i]<<" "<<c[i]<<endl;
        }
        */
    }
    return 0;
}
/*
5 5 3
2 1
3 2
1 4
5 1
1 5 4 2 3
1 3
5 3
3 3
*/

詳細信息

Test #1:

score: 100
Accepted
time: 1ms
memory: 9692kb

input:

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

output:

4
4
5

result:

ok 3 number(s): "4 4 5"

Test #2:

score: -100
Wrong Answer
time: 1ms
memory: 7784kb

input:

30 200 200
10 24
10 13
10 26
13 29
27 26
17 24
27 21
17 15
13 5
13 30
27 3
18 21
9 21
2 24
10 4
11 5
2 8
10 23
1 18
21 25
4 20
12 23
22 27
28 27
18 7
13 6
14 30
10 19
16 21
14 29 25 30 1 17 22 21 11 19 21 30 13 1 22 10 14 7 29 7 15 21 25 29 25 7 29 7 1 23 3 17 2 7 4 27 18 26 3 6 5 3 16 26 20 19 16 2...

output:

174
175
175
175
175
175
175
175
175
175
176
176
176
176
176
176
175
175
176
176
175
174
174
174
174
174
174
175
175
175
175
174
174
175
175
175
175
175
175
175
175
175
174
174
174
175
174
174
175
174
175
175
175
175
175
175
175
175
175
175
175
176
175
175
175
175
175
176
176
178
178
178
178
178
177
...

result:

wrong answer 19th numbers differ - expected: '175', found: '176'