oj.uz

Submission #968790

# Submission time Handle Problem Language Result Execution time Memory
968790 2024-04-24T04:47:18 Z yeediot Network (BOI15_net) C++17
100 / 100
 348 ms 45568 KB 
#include<bits/stdc++.h>
using namespace std;
#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:41:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   41 |     freopen((s + ".in").c_str(), "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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 + ".out").c_str(), "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 12124 KB Output is correct
2 Correct 4 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 12120 KB Output is correct
6 Correct 3 ms 12124 KB Output is correct
7 Correct 4 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 12124 KB Output is correct
12 Correct 3 ms 12124 KB Output is correct
13 Correct 3 ms 12192 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 12124 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 4 ms 12124 KB Output is correct
2 Correct 4 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 12120 KB Output is correct
6 Correct 3 ms 12124 KB Output is correct
7 Correct 4 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 12124 KB Output is correct
12 Correct 3 ms 12124 KB Output is correct
13 Correct 3 ms 12192 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 12124 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 12120 KB Output is correct
22 Correct 4 ms 12376 KB Output is correct
23 Correct 4 ms 12092 KB Output is correct
24 Correct 4 ms 12120 KB Output is correct
25 Correct 4 ms 12124 KB Output is correct
26 Correct 4 ms 12124 KB Output is correct
27 Correct 4 ms 12124 KB Output is correct
28 Correct 3 ms 12124 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 3 ms 12124 KB Output is correct
34 Correct 3 ms 12124 KB Output is correct
35 Correct 3 ms 12124 KB Output is correct
36 Correct 3 ms 12376 KB Output is correct
37 Correct 3 ms 12124 KB Output is correct
38 Correct 3 ms 12148 KB Output is correct
39 Correct 3 ms 12124 KB Output is correct
40 Correct 3 ms 12200 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 12124 KB Output is correct
44 Correct 3 ms 12124 KB Output is correct
45 Correct 3 ms 12124 KB Output is correct
46 Correct 3 ms 12120 KB Output is correct
47 Correct 3 ms 12376 KB Output is correct
48 Correct 3 ms 12376 KB Output is correct
49 Correct 3 ms 12124 KB Output is correct
50 Correct 4 ms 12120 KB Output is correct
51 Correct 3 ms 12124 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 4 ms 12140 KB Output is correct
57 Correct 3 ms 12124 KB Output is correct
58 Correct 3 ms 12124 KB Output is correct

Subtask #3
37.0 / 37.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 12124 KB Output is correct
2 Correct 4 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 12120 KB Output is correct
6 Correct 3 ms 12124 KB Output is correct
7 Correct 4 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 12124 KB Output is correct
12 Correct 3 ms 12124 KB Output is correct
13 Correct 3 ms 12192 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 12124 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 12120 KB Output is correct
22 Correct 4 ms 12376 KB Output is correct
23 Correct 4 ms 12092 KB Output is correct
24 Correct 4 ms 12120 KB Output is correct
25 Correct 4 ms 12124 KB Output is correct
26 Correct 4 ms 12124 KB Output is correct
27 Correct 4 ms 12124 KB Output is correct
28 Correct 3 ms 12124 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 3 ms 12124 KB Output is correct
34 Correct 3 ms 12124 KB Output is correct
35 Correct 3 ms 12124 KB Output is correct
36 Correct 3 ms 12376 KB Output is correct
37 Correct 3 ms 12124 KB Output is correct
38 Correct 3 ms 12148 KB Output is correct
39 Correct 3 ms 12124 KB Output is correct
40 Correct 3 ms 12200 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 12124 KB Output is correct
44 Correct 3 ms 12124 KB Output is correct
45 Correct 3 ms 12124 KB Output is correct
46 Correct 3 ms 12120 KB Output is correct
47 Correct 3 ms 12376 KB Output is correct
48 Correct 3 ms 12376 KB Output is correct
49 Correct 3 ms 12124 KB Output is correct
50 Correct 4 ms 12120 KB Output is correct
51 Correct 3 ms 12124 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 4 ms 12140 KB Output is correct
57 Correct 3 ms 12124 KB Output is correct
58 Correct 3 ms 12124 KB Output is correct
59 Correct 250 ms 29976 KB Output is correct
60 Correct 280 ms 32424 KB Output is correct
61 Correct 3 ms 12124 KB Output is correct
62 Correct 3 ms 12124 KB Output is correct
63 Correct 176 ms 28224 KB Output is correct
64 Correct 6 ms 12636 KB Output is correct
65 Correct 10 ms 13912 KB Output is correct
66 Correct 72 ms 28348 KB Output is correct
67 Correct 348 ms 44412 KB Output is correct
68 Correct 326 ms 45568 KB Output is correct
69 Correct 7 ms 12892 KB Output is correct
70 Correct 48 ms 19276 KB Output is correct
71 Correct 224 ms 35256 KB Output is correct
72 Correct 201 ms 34532 KB Output is correct
73 Correct 45 ms 17356 KB Output is correct
74 Correct 265 ms 31336 KB Output is correct
75 Correct 16 ms 14552 KB Output is correct
76 Correct 187 ms 34796 KB Output is correct
77 Correct 187 ms 35252 KB Output is correct
78 Correct 18 ms 14940 KB Output is correct
79 Correct 325 ms 42284 KB Output is correct
80 Correct 4 ms 12376 KB Output is correct
81 Correct 52 ms 19276 KB Output is correct
82 Correct 264 ms 33220 KB Output is correct
83 Correct 283 ms 31020 KB Output is correct
84 Correct 252 ms 31168 KB Output is correct
85 Correct 289 ms 31320 KB Output is correct
86 Correct 253 ms 32204 KB Output is correct
87 Correct 266 ms 32248 KB Output is correct