oj.uz

Submission #90255

# Submission time Handle Problem Language Result Execution time Memory
90255 2018-12-21T02:39:22 Z updown1 Network (BOI15_net) C++17
100 / 100
 1158 ms 168644 KB 
/*
x = total number of nodes
find a node y s.t. the max nodes in any branch is <= floor(x/2)
if x is odd, connect any leaf to y
pair leaves with leaves from different branches greedily taking the biggest two branches
*/
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define For(i, a, b) for(int i=a; i<b; i++)
#define ffi For(i, 0, N)
#define ffj For(j, 0, K)
#define ffa ffi ffj
#define s <<" "<<
#define c <<" : "<<
#define w cout
#define e endl//"\n"
#define pb push_back
#define mp make_pair
#define a first
#define b second
//#define int ll
//500,000,000 operations
const int MAXN = 500000;
//Global Variables
int N, root, x, y, leaves[MAXN], par[MAXN];
vector<int> adj[MAXN], vals[MAXN];
priority_queue<pair<int, int> > take; /// (size of queue, index)

void gol(int p, int at) {
    par[at] = p;
    if (adj[at].size() == 1) {x++; leaves[at] = 1; return;}
    for (int i: adj[at]) if (i != p) {gol(at, i); leaves[at] += leaves[i];}
}
void gorr(int p, int at, int use = -1) {
    if (use == -1 && p != -1) use=at;
    //w<< at+1 s use+1<<e;
    if (adj[at].size() == 1) vals[use].pb(at);
    for (int i: adj[at]) if (i != p) gorr(at, i, use);
}

main() {
    //ifstream cin("test.in");
    ios_base::sync_with_stdio(0); cin.tie(0);
    cin >> N;
    For (i, 1, N) {int a, b; cin >> a >> b; a--; b--; adj[a].pb(b); adj[b].pb(a);}
    ffi if (adj[i].size() != 1) root = i;
    gol(-1, root);
    ffi if (adj[i].size() != 1) {
        bool good;
        if (x-leaves[i] > (x+1)/2) good = false;
        else good = true;
        for (int j: adj[i]) if (j != par[i]) {
            if (leaves[j] > (x+1)/2) good = false;
        }
        if (good) y = i;
    }
    //w<< root+1 s x s y+1<<e;
    /// reroot the tree at y
    root = y;
    gorr(-1, y);
    for (int i: adj[y]) take.push(mp(vals[i].size(), i));
    w<< (x+1)/2<<e;
    For (i, 0, x/2) {
        int a = take.top().b; take.pop();
        int b = take.top().b; take.pop();
        w<< vals[a][vals[a].size()-1]+1 s vals[b][vals[b].size()-1]+1<<e;
        vals[a].pop_back(); vals[b].pop_back();
        take.push(mp(vals[a].size(), a)); take.push(mp(vals[b].size(), b));
    }
    if (x%2 == 1) {
        int a = take.top().b;
        w<< y+1 s vals[a].front()+1<<e;
    }
}

Compilation message

net.cpp:42:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
 main() {
      ^

Subtask #1
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 19 ms 23800 KB Output is correct
2 Correct 19 ms 23932 KB Output is correct
3 Correct 19 ms 24008 KB Output is correct
4 Correct 27 ms 24340 KB Output is correct
5 Correct 19 ms 24340 KB Output is correct
6 Correct 25 ms 24340 KB Output is correct
7 Correct 20 ms 24340 KB Output is correct
8 Correct 19 ms 24340 KB Output is correct
9 Correct 23 ms 24340 KB Output is correct
10 Correct 19 ms 24340 KB Output is correct
11 Correct 22 ms 24340 KB Output is correct
12 Correct 19 ms 24340 KB Output is correct
13 Correct 23 ms 24340 KB Output is correct
14 Correct 22 ms 24340 KB Output is correct
15 Correct 23 ms 24340 KB Output is correct
16 Correct 22 ms 24340 KB Output is correct
17 Correct 21 ms 24340 KB Output is correct
18 Correct 22 ms 24340 KB Output is correct
19 Correct 23 ms 24340 KB Output is correct
20 Correct 22 ms 24340 KB Output is correct

Subtask #2
45.0 / 45.0

# Verdict Execution time Memory Grader output
1 Correct 19 ms 23800 KB Output is correct
2 Correct 19 ms 23932 KB Output is correct
3 Correct 19 ms 24008 KB Output is correct
4 Correct 27 ms 24340 KB Output is correct
5 Correct 19 ms 24340 KB Output is correct
6 Correct 25 ms 24340 KB Output is correct
7 Correct 20 ms 24340 KB Output is correct
8 Correct 19 ms 24340 KB Output is correct
9 Correct 23 ms 24340 KB Output is correct
10 Correct 19 ms 24340 KB Output is correct
11 Correct 22 ms 24340 KB Output is correct
12 Correct 19 ms 24340 KB Output is correct
13 Correct 23 ms 24340 KB Output is correct
14 Correct 22 ms 24340 KB Output is correct
15 Correct 23 ms 24340 KB Output is correct
16 Correct 22 ms 24340 KB Output is correct
17 Correct 21 ms 24340 KB Output is correct
18 Correct 22 ms 24340 KB Output is correct
19 Correct 23 ms 24340 KB Output is correct
20 Correct 22 ms 24340 KB Output is correct
21 Correct 22 ms 24340 KB Output is correct
22 Correct 25 ms 24340 KB Output is correct
23 Correct 25 ms 24340 KB Output is correct
24 Correct 26 ms 24340 KB Output is correct
25 Correct 23 ms 24340 KB Output is correct
26 Correct 24 ms 24340 KB Output is correct
27 Correct 24 ms 24340 KB Output is correct
28 Correct 24 ms 24340 KB Output is correct
29 Correct 20 ms 24340 KB Output is correct
30 Correct 22 ms 24340 KB Output is correct
31 Correct 25 ms 24340 KB Output is correct
32 Correct 23 ms 24340 KB Output is correct
33 Correct 22 ms 24340 KB Output is correct
34 Correct 22 ms 24340 KB Output is correct
35 Correct 22 ms 24340 KB Output is correct
36 Correct 22 ms 24340 KB Output is correct
37 Correct 21 ms 24340 KB Output is correct
38 Correct 24 ms 24340 KB Output is correct
39 Correct 22 ms 24340 KB Output is correct
40 Correct 23 ms 24340 KB Output is correct
41 Correct 22 ms 24340 KB Output is correct
42 Correct 23 ms 24340 KB Output is correct
43 Correct 20 ms 24340 KB Output is correct
44 Correct 23 ms 24340 KB Output is correct
45 Correct 22 ms 24340 KB Output is correct
46 Correct 20 ms 24340 KB Output is correct
47 Correct 22 ms 24340 KB Output is correct
48 Correct 23 ms 24340 KB Output is correct
49 Correct 24 ms 24340 KB Output is correct
50 Correct 23 ms 24340 KB Output is correct
51 Correct 22 ms 24340 KB Output is correct
52 Correct 23 ms 24340 KB Output is correct
53 Correct 24 ms 24340 KB Output is correct
54 Correct 23 ms 24340 KB Output is correct
55 Correct 22 ms 24340 KB Output is correct
56 Correct 23 ms 24340 KB Output is correct
57 Correct 23 ms 24340 KB Output is correct
58 Correct 25 ms 24340 KB Output is correct

Subtask #3
37.0 / 37.0

# Verdict Execution time Memory Grader output
1 Correct 19 ms 23800 KB Output is correct
2 Correct 19 ms 23932 KB Output is correct
3 Correct 19 ms 24008 KB Output is correct
4 Correct 27 ms 24340 KB Output is correct
5 Correct 19 ms 24340 KB Output is correct
6 Correct 25 ms 24340 KB Output is correct
7 Correct 20 ms 24340 KB Output is correct
8 Correct 19 ms 24340 KB Output is correct
9 Correct 23 ms 24340 KB Output is correct
10 Correct 19 ms 24340 KB Output is correct
11 Correct 22 ms 24340 KB Output is correct
12 Correct 19 ms 24340 KB Output is correct
13 Correct 23 ms 24340 KB Output is correct
14 Correct 22 ms 24340 KB Output is correct
15 Correct 23 ms 24340 KB Output is correct
16 Correct 22 ms 24340 KB Output is correct
17 Correct 21 ms 24340 KB Output is correct
18 Correct 22 ms 24340 KB Output is correct
19 Correct 23 ms 24340 KB Output is correct
20 Correct 22 ms 24340 KB Output is correct
21 Correct 22 ms 24340 KB Output is correct
22 Correct 25 ms 24340 KB Output is correct
23 Correct 25 ms 24340 KB Output is correct
24 Correct 26 ms 24340 KB Output is correct
25 Correct 23 ms 24340 KB Output is correct
26 Correct 24 ms 24340 KB Output is correct
27 Correct 24 ms 24340 KB Output is correct
28 Correct 24 ms 24340 KB Output is correct
29 Correct 20 ms 24340 KB Output is correct
30 Correct 22 ms 24340 KB Output is correct
31 Correct 25 ms 24340 KB Output is correct
32 Correct 23 ms 24340 KB Output is correct
33 Correct 22 ms 24340 KB Output is correct
34 Correct 22 ms 24340 KB Output is correct
35 Correct 22 ms 24340 KB Output is correct
36 Correct 22 ms 24340 KB Output is correct
37 Correct 21 ms 24340 KB Output is correct
38 Correct 24 ms 24340 KB Output is correct
39 Correct 22 ms 24340 KB Output is correct
40 Correct 23 ms 24340 KB Output is correct
41 Correct 22 ms 24340 KB Output is correct
42 Correct 23 ms 24340 KB Output is correct
43 Correct 20 ms 24340 KB Output is correct
44 Correct 23 ms 24340 KB Output is correct
45 Correct 22 ms 24340 KB Output is correct
46 Correct 20 ms 24340 KB Output is correct
47 Correct 22 ms 24340 KB Output is correct
48 Correct 23 ms 24340 KB Output is correct
49 Correct 24 ms 24340 KB Output is correct
50 Correct 23 ms 24340 KB Output is correct
51 Correct 22 ms 24340 KB Output is correct
52 Correct 23 ms 24340 KB Output is correct
53 Correct 24 ms 24340 KB Output is correct
54 Correct 23 ms 24340 KB Output is correct
55 Correct 22 ms 24340 KB Output is correct
56 Correct 23 ms 24340 KB Output is correct
57 Correct 23 ms 24340 KB Output is correct
58 Correct 25 ms 24340 KB Output is correct
59 Correct 936 ms 56432 KB Output is correct
60 Correct 785 ms 61180 KB Output is correct
61 Correct 19 ms 61180 KB Output is correct
62 Correct 19 ms 61180 KB Output is correct
63 Correct 703 ms 64268 KB Output is correct
64 Correct 22 ms 64268 KB Output is correct
65 Correct 87 ms 64268 KB Output is correct
66 Correct 231 ms 64268 KB Output is correct
67 Correct 892 ms 102360 KB Output is correct
68 Correct 888 ms 102360 KB Output is correct
69 Correct 44 ms 102360 KB Output is correct
70 Correct 293 ms 102360 KB Output is correct
71 Correct 1115 ms 111552 KB Output is correct
72 Correct 1158 ms 115232 KB Output is correct
73 Correct 183 ms 115232 KB Output is correct
74 Correct 851 ms 115232 KB Output is correct
75 Correct 101 ms 115232 KB Output is correct
76 Correct 1064 ms 124092 KB Output is correct
77 Correct 1057 ms 131160 KB Output is correct
78 Correct 68 ms 131160 KB Output is correct
79 Correct 815 ms 136640 KB Output is correct
80 Correct 28 ms 136640 KB Output is correct
81 Correct 294 ms 136640 KB Output is correct
82 Correct 943 ms 145084 KB Output is correct
83 Correct 754 ms 145084 KB Output is correct
84 Correct 777 ms 147748 KB Output is correct
85 Correct 769 ms 154532 KB Output is correct
86 Correct 883 ms 161904 KB Output is correct
87 Correct 887 ms 168644 KB Output is correct