oj.uz

Submission #968789

# Submission time Handle Problem Language Result Execution time Memory
968789 2024-04-24T04:44:47 Z yeediot Network (BOI15_net) C++17
100 / 100
 380 ms 53196 KB 
#include<bits/stdc++.h>
using namespace std;
#define int long long
#define F first
#define S second
#define all(x) x.begin(),x.end()
#define pii pair<int,int>
#define pb push_back
#define sz(x) (int)(x.size())
#define chmin(x,y) x=min(x,y)
#define chmax(x,y) x=max(x,y)
#define vi vector<int>
#define vp vector<pii>
#define vvi vector<vi>
#define ykh mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count())
#define __lg(x) 63-__builtin_clzll(x)
#define pow2(x) (1LL<<x)
void __print(int x) {cerr << x;}
void __print(float x) {cerr << x;}
void __print(double x) {cerr << x;}
void __print(long double x) {cerr << x;}
void __print(char x) {cerr << '\'' << x << '\'';}
void __print(const char *x) {cerr << '\"' << x << '\"';}
void __print(const string &x) {cerr << '\"' << x << '\"';}
void __print(bool x) {cerr << (x ? "true" : "false");}

template<typename T, typename V>
void __print(const pair<T, V> &x) {cerr << '{'; __print(x.first); cerr << ','; __print(x.second); cerr << '}';}
template<typename T>
void __print(const T &x) {int f = 0; cerr << '{'; for (auto &i: x) cerr << (f++ ? "," : ""), __print(i); cerr << "}";}
void _print() {cerr << "]\n";}
template <typename T, typename... V>
void _print(T t, V... v) {__print(t); if (sizeof...(v)) cerr << ", "; _print(v...);}
#ifdef local
void setio(){freopen("/Users/iantsai/Library/Mobile Documents/com~apple~CloudDocs/cpp/Empty.md","r",stdin);}
#define debug(x...) cerr << "[" << #x << "] = ["; _print(x)
#else
void setio(){}
#define debug(x...)
#endif
void setIO(string s) {
    freopen((s + ".in").c_str(), "r", stdin);
    freopen((s + ".out").c_str(), "w", stdout);
}
struct line{
    int a,b;
    int operator()(const int x)const{
        return a*x+b;
    }
};
bool check(line l1,line l2,line l3){
    return (l3.b-l2.b)*(l1.a-l2.a)<=(l2.b-l1.b)*(l2.a-l3.a);
}
const int mxn=5e5+5;
vector<int>adj[mxn];
int cnt=0;
vector<int>leaves;
void dfs(int v,int pa){
    for(auto u:adj[v]){
        if(u==pa)continue;
        dfs(u,v);
    }
    if(sz(adj[v])==1){
        leaves.pb(v);
    }
}
signed main(){
    setio();
    ios::sync_with_stdio(0);
    cin.tie(0);cout.tie(0);
    int n;
    cin>>n;
    for(int i=1;i<n;i++){
        int a,b;
        cin>>a>>b;
        adj[a].pb(b);
        adj[b].pb(a);
    }
    dfs(1,-1);
    cout<<(sz(leaves)+1)/2<<'\n';
    for(int i=0;i<sz(leaves)/2;i++){
        cout<<leaves[i]<<' '<<leaves[i+sz(leaves)/2]<<'\n';
        if(i==0 and sz(leaves)%2){
            cout<<leaves[0]<<' '<<leaves.back()<<'\n';
        }
    }
}
 /*
 input:
 
 */

Compilation message

net.cpp: In function 'void setIO(std::string)':
net.cpp:42:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   42 |     freopen((s + ".in").c_str(), "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
net.cpp:43:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   43 |     freopen((s + ".out").c_str(), "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 12124 KB Output is correct
2 Correct 3 ms 12124 KB Output is correct
3 Correct 3 ms 12124 KB Output is correct
4 Correct 3 ms 12124 KB Output is correct
5 Correct 3 ms 12372 KB Output is correct
6 Correct 4 ms 12124 KB Output is correct
7 Correct 3 ms 12124 KB Output is correct
8 Correct 3 ms 12120 KB Output is correct
9 Correct 3 ms 12124 KB Output is correct
10 Correct 3 ms 12124 KB Output is correct
11 Correct 3 ms 12120 KB Output is correct
12 Correct 3 ms 12124 KB Output is correct
13 Correct 3 ms 12124 KB Output is correct
14 Correct 3 ms 12124 KB Output is correct
15 Correct 3 ms 12124 KB Output is correct
16 Correct 3 ms 12120 KB Output is correct
17 Correct 3 ms 12120 KB Output is correct
18 Correct 3 ms 12124 KB Output is correct
19 Correct 3 ms 12124 KB Output is correct
20 Correct 3 ms 12124 KB Output is correct

Subtask #2
45.0 / 45.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 12124 KB Output is correct
2 Correct 3 ms 12124 KB Output is correct
3 Correct 3 ms 12124 KB Output is correct
4 Correct 3 ms 12124 KB Output is correct
5 Correct 3 ms 12372 KB Output is correct
6 Correct 4 ms 12124 KB Output is correct
7 Correct 3 ms 12124 KB Output is correct
8 Correct 3 ms 12120 KB Output is correct
9 Correct 3 ms 12124 KB Output is correct
10 Correct 3 ms 12124 KB Output is correct
11 Correct 3 ms 12120 KB Output is correct
12 Correct 3 ms 12124 KB Output is correct
13 Correct 3 ms 12124 KB Output is correct
14 Correct 3 ms 12124 KB Output is correct
15 Correct 3 ms 12124 KB Output is correct
16 Correct 3 ms 12120 KB Output is correct
17 Correct 3 ms 12120 KB Output is correct
18 Correct 3 ms 12124 KB Output is correct
19 Correct 3 ms 12124 KB Output is correct
20 Correct 3 ms 12124 KB Output is correct
21 Correct 3 ms 12376 KB Output is correct
22 Correct 3 ms 12124 KB Output is correct
23 Correct 4 ms 12120 KB Output is correct
24 Correct 3 ms 12124 KB Output is correct
25 Correct 3 ms 12124 KB Output is correct
26 Correct 3 ms 12124 KB Output is correct
27 Correct 4 ms 12124 KB Output is correct
28 Correct 4 ms 12140 KB Output is correct
29 Correct 3 ms 12124 KB Output is correct
30 Correct 3 ms 12124 KB Output is correct
31 Correct 3 ms 12124 KB Output is correct
32 Correct 3 ms 12124 KB Output is correct
33 Correct 4 ms 12124 KB Output is correct
34 Correct 3 ms 12120 KB Output is correct
35 Correct 3 ms 12320 KB Output is correct
36 Correct 3 ms 12124 KB Output is correct
37 Correct 3 ms 12124 KB Output is correct
38 Correct 4 ms 12140 KB Output is correct
39 Correct 3 ms 12124 KB Output is correct
40 Correct 3 ms 12124 KB Output is correct
41 Correct 3 ms 12124 KB Output is correct
42 Correct 3 ms 12124 KB Output is correct
43 Correct 3 ms 12120 KB Output is correct
44 Correct 3 ms 12120 KB Output is correct
45 Correct 3 ms 12136 KB Output is correct
46 Correct 3 ms 12124 KB Output is correct
47 Correct 3 ms 12124 KB Output is correct
48 Correct 3 ms 12120 KB Output is correct
49 Correct 4 ms 12124 KB Output is correct
50 Correct 3 ms 12124 KB Output is correct
51 Correct 3 ms 12120 KB Output is correct
52 Correct 3 ms 12124 KB Output is correct
53 Correct 3 ms 12124 KB Output is correct
54 Correct 3 ms 12124 KB Output is correct
55 Correct 3 ms 12124 KB Output is correct
56 Correct 3 ms 12120 KB Output is correct
57 Correct 3 ms 12124 KB Output is correct
58 Correct 3 ms 12120 KB Output is correct

Subtask #3
37.0 / 37.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 12124 KB Output is correct
2 Correct 3 ms 12124 KB Output is correct
3 Correct 3 ms 12124 KB Output is correct
4 Correct 3 ms 12124 KB Output is correct
5 Correct 3 ms 12372 KB Output is correct
6 Correct 4 ms 12124 KB Output is correct
7 Correct 3 ms 12124 KB Output is correct
8 Correct 3 ms 12120 KB Output is correct
9 Correct 3 ms 12124 KB Output is correct
10 Correct 3 ms 12124 KB Output is correct
11 Correct 3 ms 12120 KB Output is correct
12 Correct 3 ms 12124 KB Output is correct
13 Correct 3 ms 12124 KB Output is correct
14 Correct 3 ms 12124 KB Output is correct
15 Correct 3 ms 12124 KB Output is correct
16 Correct 3 ms 12120 KB Output is correct
17 Correct 3 ms 12120 KB Output is correct
18 Correct 3 ms 12124 KB Output is correct
19 Correct 3 ms 12124 KB Output is correct
20 Correct 3 ms 12124 KB Output is correct
21 Correct 3 ms 12376 KB Output is correct
22 Correct 3 ms 12124 KB Output is correct
23 Correct 4 ms 12120 KB Output is correct
24 Correct 3 ms 12124 KB Output is correct
25 Correct 3 ms 12124 KB Output is correct
26 Correct 3 ms 12124 KB Output is correct
27 Correct 4 ms 12124 KB Output is correct
28 Correct 4 ms 12140 KB Output is correct
29 Correct 3 ms 12124 KB Output is correct
30 Correct 3 ms 12124 KB Output is correct
31 Correct 3 ms 12124 KB Output is correct
32 Correct 3 ms 12124 KB Output is correct
33 Correct 4 ms 12124 KB Output is correct
34 Correct 3 ms 12120 KB Output is correct
35 Correct 3 ms 12320 KB Output is correct
36 Correct 3 ms 12124 KB Output is correct
37 Correct 3 ms 12124 KB Output is correct
38 Correct 4 ms 12140 KB Output is correct
39 Correct 3 ms 12124 KB Output is correct
40 Correct 3 ms 12124 KB Output is correct
41 Correct 3 ms 12124 KB Output is correct
42 Correct 3 ms 12124 KB Output is correct
43 Correct 3 ms 12120 KB Output is correct
44 Correct 3 ms 12120 KB Output is correct
45 Correct 3 ms 12136 KB Output is correct
46 Correct 3 ms 12124 KB Output is correct
47 Correct 3 ms 12124 KB Output is correct
48 Correct 3 ms 12120 KB Output is correct
49 Correct 4 ms 12124 KB Output is correct
50 Correct 3 ms 12124 KB Output is correct
51 Correct 3 ms 12120 KB Output is correct
52 Correct 3 ms 12124 KB Output is correct
53 Correct 3 ms 12124 KB Output is correct
54 Correct 3 ms 12124 KB Output is correct
55 Correct 3 ms 12124 KB Output is correct
56 Correct 3 ms 12120 KB Output is correct
57 Correct 3 ms 12124 KB Output is correct
58 Correct 3 ms 12120 KB Output is correct
59 Correct 237 ms 42176 KB Output is correct
60 Correct 287 ms 43448 KB Output is correct
61 Correct 3 ms 12124 KB Output is correct
62 Correct 3 ms 12124 KB Output is correct
63 Correct 215 ms 37196 KB Output is correct
64 Correct 5 ms 12636 KB Output is correct
65 Correct 10 ms 14256 KB Output is correct
66 Correct 69 ms 30548 KB Output is correct
67 Correct 380 ms 51088 KB Output is correct
68 Correct 351 ms 53196 KB Output is correct
69 Correct 7 ms 13148 KB Output is correct
70 Correct 51 ms 23344 KB Output is correct
71 Correct 188 ms 45872 KB Output is correct
72 Correct 191 ms 45064 KB Output is correct
73 Correct 49 ms 20168 KB Output is correct
74 Correct 297 ms 41164 KB Output is correct
75 Correct 24 ms 15828 KB Output is correct
76 Correct 202 ms 45480 KB Output is correct
77 Correct 214 ms 45848 KB Output is correct
78 Correct 20 ms 15836 KB Output is correct
79 Correct 370 ms 48980 KB Output is correct
80 Correct 6 ms 12376 KB Output is correct
81 Correct 57 ms 22604 KB Output is correct
82 Correct 258 ms 43836 KB Output is correct
83 Correct 297 ms 41484 KB Output is correct
84 Correct 302 ms 41516 KB Output is correct
85 Correct 280 ms 41156 KB Output is correct
86 Correct 263 ms 43452 KB Output is correct
87 Correct 271 ms 44296 KB Output is correct