oj.uz

Submission #40617

# Submission time Handle Problem Language Result Execution time Memory
40617 2018-02-05T17:07:03 Z Hassoony Network (BOI15_net) C++14
100 / 100
 1034 ms 175436 KB 
#include<bits/stdc++.h>
#include<unordered_map>
using namespace std;
typedef long long ll;
const ll inf=(1ll<<60);
const ll mod=1e9+7;
const int MX=6e5+9;
int n,subtree[MX],par[MX],leaf[MX],ans;
vector<int>v[MX],v1[MX];
void dfs_size(int x,int p){
    subtree[x]=leaf[x];
    par[x]=p;
    for(auto pp:v[x]){
        if(pp==p)continue;
        dfs_size(pp,x);
        subtree[x]+=subtree[pp];
    }
}
int centroid(int x){
    dfs_size(x,-1);
    int S=subtree[x],idx=1;
    queue<int>q;
    q.push(x);
    while(!q.empty()){
        int nxt=q.front();q.pop();
        int s=subtree[x]-subtree[nxt];
        for(auto pp:v[nxt]){
            if(pp==par[nxt])continue;
            s=max(s,subtree[pp]);
            q.push(pp);
        }
        if(S>s){
            S=s;
            idx=nxt;
        }
    }
    return idx;
}
int x,y,cen=1,timer;
void dfs(int x,int p){
    if(leaf[x]){
        v1[timer].push_back(x);
        return;
    }
    for(auto pp:v[x]){
        if(pp==p)continue;
        dfs(pp,x);
        if(x==cen)timer++;
    }
}
int leaves;
int cel(int x,int y){
    if(x%y==0)return x/y;
    return x/y+1;
}
int main(){
    scanf("%d",&n);
    for(int i=0;i<n-1;i++){
        scanf("%d%d",&x,&y);
        v[x].push_back(y);
        v[y].push_back(x);
    }
    for(int i=1;i<=n;i++){
        if(v[i].size()==1){
            leaf[i]=1;
            leaves++;
        }
    }
    int idx=1;
    for(int i=1;i<=n;i++)if(!leaf[i])idx=i;
    ans=cel(leaves,2);
    cen=centroid(idx);
    dfs(cen,-1);
    priority_queue<pair<int,int> >pq;
    for(int i=0;i<timer;i++){
        pq.push({v1[i].size(),i});
    }
    printf("%d\n",ans);
    while(pq.size()>1){
        int com1=pq.top().second,sz1=pq.top().first;pq.pop();
        int com2=pq.top().second,sz2=pq.top().first;pq.pop();
        if(sz1<=0||sz2<=0)continue;
        printf("%d %d\n",v1[com1].back(),v1[com2].back());
        v1[com1].pop_back();sz1--;
        v1[com2].pop_back();sz2--;
        if(sz1>0)pq.push({sz1,com1});
        if(sz2>0)pq.push({sz2,com2});
    }
    if(pq.size()==1){
        printf("%d %d",v1[pq.top().second][0],cen);
    }
}

Compilation message

net.cpp: In function 'int main()':
net.cpp:57:19: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d",&n);
                   ^
net.cpp:59:28: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d%d",&x,&y);
                            ^

Subtask #1
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 26 ms 28536 KB Output is correct
2 Correct 25 ms 28640 KB Output is correct
3 Correct 25 ms 28640 KB Output is correct
4 Correct 29 ms 28640 KB Output is correct
5 Correct 24 ms 28720 KB Output is correct
6 Correct 25 ms 28720 KB Output is correct
7 Correct 24 ms 28720 KB Output is correct
8 Correct 25 ms 28720 KB Output is correct
9 Correct 24 ms 28720 KB Output is correct
10 Correct 25 ms 28760 KB Output is correct
11 Correct 25 ms 28764 KB Output is correct
12 Correct 25 ms 28764 KB Output is correct
13 Correct 25 ms 28764 KB Output is correct
14 Correct 27 ms 28764 KB Output is correct
15 Correct 25 ms 28892 KB Output is correct
16 Correct 25 ms 28892 KB Output is correct
17 Correct 25 ms 28892 KB Output is correct
18 Correct 25 ms 28892 KB Output is correct
19 Correct 25 ms 28892 KB Output is correct
20 Correct 24 ms 28892 KB Output is correct

Subtask #2
45.0 / 45.0

# Verdict Execution time Memory Grader output
1 Correct 26 ms 28536 KB Output is correct
2 Correct 25 ms 28640 KB Output is correct
3 Correct 25 ms 28640 KB Output is correct
4 Correct 29 ms 28640 KB Output is correct
5 Correct 24 ms 28720 KB Output is correct
6 Correct 25 ms 28720 KB Output is correct
7 Correct 24 ms 28720 KB Output is correct
8 Correct 25 ms 28720 KB Output is correct
9 Correct 24 ms 28720 KB Output is correct
10 Correct 25 ms 28760 KB Output is correct
11 Correct 25 ms 28764 KB Output is correct
12 Correct 25 ms 28764 KB Output is correct
13 Correct 25 ms 28764 KB Output is correct
14 Correct 27 ms 28764 KB Output is correct
15 Correct 25 ms 28892 KB Output is correct
16 Correct 25 ms 28892 KB Output is correct
17 Correct 25 ms 28892 KB Output is correct
18 Correct 25 ms 28892 KB Output is correct
19 Correct 25 ms 28892 KB Output is correct
20 Correct 24 ms 28892 KB Output is correct
21 Correct 26 ms 28892 KB Output is correct
22 Correct 28 ms 28892 KB Output is correct
23 Correct 28 ms 28892 KB Output is correct
24 Correct 26 ms 28908 KB Output is correct
25 Correct 32 ms 28924 KB Output is correct
26 Correct 26 ms 28924 KB Output is correct
27 Correct 26 ms 28924 KB Output is correct
28 Correct 25 ms 28924 KB Output is correct
29 Correct 25 ms 28924 KB Output is correct
30 Correct 25 ms 28924 KB Output is correct
31 Correct 26 ms 28940 KB Output is correct
32 Correct 24 ms 28940 KB Output is correct
33 Correct 25 ms 28940 KB Output is correct
34 Correct 25 ms 28940 KB Output is correct
35 Correct 26 ms 28940 KB Output is correct
36 Correct 28 ms 28940 KB Output is correct
37 Correct 25 ms 28940 KB Output is correct
38 Correct 25 ms 28992 KB Output is correct
39 Correct 25 ms 28992 KB Output is correct
40 Correct 25 ms 28992 KB Output is correct
41 Correct 25 ms 28992 KB Output is correct
42 Correct 25 ms 28992 KB Output is correct
43 Correct 26 ms 28992 KB Output is correct
44 Correct 25 ms 28992 KB Output is correct
45 Correct 28 ms 28992 KB Output is correct
46 Correct 27 ms 28992 KB Output is correct
47 Correct 25 ms 28992 KB Output is correct
48 Correct 25 ms 28992 KB Output is correct
49 Correct 25 ms 28992 KB Output is correct
50 Correct 25 ms 28992 KB Output is correct
51 Correct 25 ms 28992 KB Output is correct
52 Correct 25 ms 28992 KB Output is correct
53 Correct 26 ms 29012 KB Output is correct
54 Correct 24 ms 29012 KB Output is correct
55 Correct 24 ms 29012 KB Output is correct
56 Correct 26 ms 29012 KB Output is correct
57 Correct 26 ms 29012 KB Output is correct
58 Correct 27 ms 29060 KB Output is correct

Subtask #3
37.0 / 37.0

# Verdict Execution time Memory Grader output
1 Correct 26 ms 28536 KB Output is correct
2 Correct 25 ms 28640 KB Output is correct
3 Correct 25 ms 28640 KB Output is correct
4 Correct 29 ms 28640 KB Output is correct
5 Correct 24 ms 28720 KB Output is correct
6 Correct 25 ms 28720 KB Output is correct
7 Correct 24 ms 28720 KB Output is correct
8 Correct 25 ms 28720 KB Output is correct
9 Correct 24 ms 28720 KB Output is correct
10 Correct 25 ms 28760 KB Output is correct
11 Correct 25 ms 28764 KB Output is correct
12 Correct 25 ms 28764 KB Output is correct
13 Correct 25 ms 28764 KB Output is correct
14 Correct 27 ms 28764 KB Output is correct
15 Correct 25 ms 28892 KB Output is correct
16 Correct 25 ms 28892 KB Output is correct
17 Correct 25 ms 28892 KB Output is correct
18 Correct 25 ms 28892 KB Output is correct
19 Correct 25 ms 28892 KB Output is correct
20 Correct 24 ms 28892 KB Output is correct
21 Correct 26 ms 28892 KB Output is correct
22 Correct 28 ms 28892 KB Output is correct
23 Correct 28 ms 28892 KB Output is correct
24 Correct 26 ms 28908 KB Output is correct
25 Correct 32 ms 28924 KB Output is correct
26 Correct 26 ms 28924 KB Output is correct
27 Correct 26 ms 28924 KB Output is correct
28 Correct 25 ms 28924 KB Output is correct
29 Correct 25 ms 28924 KB Output is correct
30 Correct 25 ms 28924 KB Output is correct
31 Correct 26 ms 28940 KB Output is correct
32 Correct 24 ms 28940 KB Output is correct
33 Correct 25 ms 28940 KB Output is correct
34 Correct 25 ms 28940 KB Output is correct
35 Correct 26 ms 28940 KB Output is correct
36 Correct 28 ms 28940 KB Output is correct
37 Correct 25 ms 28940 KB Output is correct
38 Correct 25 ms 28992 KB Output is correct
39 Correct 25 ms 28992 KB Output is correct
40 Correct 25 ms 28992 KB Output is correct
41 Correct 25 ms 28992 KB Output is correct
42 Correct 25 ms 28992 KB Output is correct
43 Correct 26 ms 28992 KB Output is correct
44 Correct 25 ms 28992 KB Output is correct
45 Correct 28 ms 28992 KB Output is correct
46 Correct 27 ms 28992 KB Output is correct
47 Correct 25 ms 28992 KB Output is correct
48 Correct 25 ms 28992 KB Output is correct
49 Correct 25 ms 28992 KB Output is correct
50 Correct 25 ms 28992 KB Output is correct
51 Correct 25 ms 28992 KB Output is correct
52 Correct 25 ms 28992 KB Output is correct
53 Correct 26 ms 29012 KB Output is correct
54 Correct 24 ms 29012 KB Output is correct
55 Correct 24 ms 29012 KB Output is correct
56 Correct 26 ms 29012 KB Output is correct
57 Correct 26 ms 29012 KB Output is correct
58 Correct 27 ms 29060 KB Output is correct
59 Correct 688 ms 62884 KB Output is correct
60 Correct 745 ms 67700 KB Output is correct
61 Correct 25 ms 67700 KB Output is correct
62 Correct 24 ms 67700 KB Output is correct
63 Correct 556 ms 70644 KB Output is correct
64 Correct 28 ms 70644 KB Output is correct
65 Correct 41 ms 70644 KB Output is correct
66 Correct 289 ms 70644 KB Output is correct
67 Correct 1034 ms 106888 KB Output is correct
68 Correct 982 ms 106888 KB Output is correct
69 Correct 37 ms 106888 KB Output is correct
70 Correct 199 ms 106888 KB Output is correct
71 Correct 596 ms 118120 KB Output is correct
72 Correct 643 ms 121960 KB Output is correct
73 Correct 154 ms 121960 KB Output is correct
74 Correct 767 ms 121960 KB Output is correct
75 Correct 71 ms 121960 KB Output is correct
76 Correct 589 ms 130728 KB Output is correct
77 Correct 501 ms 137932 KB Output is correct
78 Correct 66 ms 137932 KB Output is correct
79 Correct 847 ms 141504 KB Output is correct
80 Correct 26 ms 141504 KB Output is correct
81 Correct 182 ms 141504 KB Output is correct
82 Correct 640 ms 151752 KB Output is correct
83 Correct 702 ms 151752 KB Output is correct
84 Correct 721 ms 154412 KB Output is correct
85 Correct 726 ms 161264 KB Output is correct
86 Correct 701 ms 168624 KB Output is correct
87 Correct 688 ms 175436 KB Output is correct