oj.uz

Submission #968788

# Submission time Handle Problem Language Result Execution time Memory
968788 2024-04-24T04:44:16 Z yeediot Network (BOI15_net) C++17
63 / 100
 5 ms 10076 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=2e5+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 1 ms 4956 KB Output is correct
2 Correct 1 ms 4956 KB Output is correct
3 Correct 1 ms 4956 KB Output is correct
4 Correct 1 ms 4956 KB Output is correct
5 Correct 1 ms 4956 KB Output is correct
6 Correct 2 ms 4956 KB Output is correct
7 Correct 1 ms 4956 KB Output is correct
8 Correct 1 ms 4956 KB Output is correct
9 Correct 2 ms 4952 KB Output is correct
10 Correct 2 ms 4956 KB Output is correct
11 Correct 2 ms 4956 KB Output is correct
12 Correct 1 ms 4956 KB Output is correct
13 Correct 2 ms 4952 KB Output is correct
14 Correct 2 ms 4956 KB Output is correct
15 Correct 2 ms 4956 KB Output is correct
16 Correct 2 ms 4956 KB Output is correct
17 Correct 1 ms 5156 KB Output is correct
18 Correct 1 ms 4956 KB Output is correct
19 Correct 2 ms 4956 KB Output is correct
20 Correct 1 ms 4956 KB Output is correct

Subtask #2
45.0 / 45.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 4956 KB Output is correct
2 Correct 1 ms 4956 KB Output is correct
3 Correct 1 ms 4956 KB Output is correct
4 Correct 1 ms 4956 KB Output is correct
5 Correct 1 ms 4956 KB Output is correct
6 Correct 2 ms 4956 KB Output is correct
7 Correct 1 ms 4956 KB Output is correct
8 Correct 1 ms 4956 KB Output is correct
9 Correct 2 ms 4952 KB Output is correct
10 Correct 2 ms 4956 KB Output is correct
11 Correct 2 ms 4956 KB Output is correct
12 Correct 1 ms 4956 KB Output is correct
13 Correct 2 ms 4952 KB Output is correct
14 Correct 2 ms 4956 KB Output is correct
15 Correct 2 ms 4956 KB Output is correct
16 Correct 2 ms 4956 KB Output is correct
17 Correct 1 ms 5156 KB Output is correct
18 Correct 1 ms 4956 KB Output is correct
19 Correct 2 ms 4956 KB Output is correct
20 Correct 1 ms 4956 KB Output is correct
21 Correct 2 ms 4956 KB Output is correct
22 Correct 2 ms 5212 KB Output is correct
23 Correct 2 ms 5212 KB Output is correct
24 Correct 2 ms 5212 KB Output is correct
25 Correct 2 ms 5212 KB Output is correct
26 Correct 2 ms 5212 KB Output is correct
27 Correct 2 ms 5212 KB Output is correct
28 Correct 2 ms 5208 KB Output is correct
29 Correct 2 ms 5212 KB Output is correct
30 Correct 1 ms 4956 KB Output is correct
31 Correct 2 ms 5212 KB Output is correct
32 Correct 1 ms 4956 KB Output is correct
33 Correct 2 ms 4960 KB Output is correct
34 Correct 1 ms 5156 KB Output is correct
35 Correct 1 ms 4956 KB Output is correct
36 Correct 1 ms 4956 KB Output is correct
37 Correct 2 ms 4956 KB Output is correct
38 Correct 2 ms 5212 KB Output is correct
39 Correct 1 ms 4956 KB Output is correct
40 Correct 1 ms 4956 KB Output is correct
41 Correct 1 ms 4952 KB Output is correct
42 Correct 2 ms 4952 KB Output is correct
43 Correct 2 ms 5212 KB Output is correct
44 Correct 1 ms 4956 KB Output is correct
45 Correct 2 ms 4956 KB Output is correct
46 Correct 2 ms 4956 KB Output is correct
47 Correct 1 ms 4956 KB Output is correct
48 Correct 2 ms 4956 KB Output is correct
49 Correct 2 ms 5212 KB Output is correct
50 Correct 1 ms 4952 KB Output is correct
51 Correct 1 ms 4956 KB Output is correct
52 Correct 1 ms 4956 KB Output is correct
53 Correct 2 ms 5212 KB Output is correct
54 Correct 2 ms 5152 KB Output is correct
55 Correct 2 ms 4956 KB Output is correct
56 Correct 1 ms 4956 KB Output is correct
57 Correct 2 ms 4956 KB Output is correct
58 Correct 2 ms 5212 KB Output is correct

Subtask #3
0 / 37.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 4956 KB Output is correct
2 Correct 1 ms 4956 KB Output is correct
3 Correct 1 ms 4956 KB Output is correct
4 Correct 1 ms 4956 KB Output is correct
5 Correct 1 ms 4956 KB Output is correct
6 Correct 2 ms 4956 KB Output is correct
7 Correct 1 ms 4956 KB Output is correct
8 Correct 1 ms 4956 KB Output is correct
9 Correct 2 ms 4952 KB Output is correct
10 Correct 2 ms 4956 KB Output is correct
11 Correct 2 ms 4956 KB Output is correct
12 Correct 1 ms 4956 KB Output is correct
13 Correct 2 ms 4952 KB Output is correct
14 Correct 2 ms 4956 KB Output is correct
15 Correct 2 ms 4956 KB Output is correct
16 Correct 2 ms 4956 KB Output is correct
17 Correct 1 ms 5156 KB Output is correct
18 Correct 1 ms 4956 KB Output is correct
19 Correct 2 ms 4956 KB Output is correct
20 Correct 1 ms 4956 KB Output is correct
21 Correct 2 ms 4956 KB Output is correct
22 Correct 2 ms 5212 KB Output is correct
23 Correct 2 ms 5212 KB Output is correct
24 Correct 2 ms 5212 KB Output is correct
25 Correct 2 ms 5212 KB Output is correct
26 Correct 2 ms 5212 KB Output is correct
27 Correct 2 ms 5212 KB Output is correct
28 Correct 2 ms 5208 KB Output is correct
29 Correct 2 ms 5212 KB Output is correct
30 Correct 1 ms 4956 KB Output is correct
31 Correct 2 ms 5212 KB Output is correct
32 Correct 1 ms 4956 KB Output is correct
33 Correct 2 ms 4960 KB Output is correct
34 Correct 1 ms 5156 KB Output is correct
35 Correct 1 ms 4956 KB Output is correct
36 Correct 1 ms 4956 KB Output is correct
37 Correct 2 ms 4956 KB Output is correct
38 Correct 2 ms 5212 KB Output is correct
39 Correct 1 ms 4956 KB Output is correct
40 Correct 1 ms 4956 KB Output is correct
41 Correct 1 ms 4952 KB Output is correct
42 Correct 2 ms 4952 KB Output is correct
43 Correct 2 ms 5212 KB Output is correct
44 Correct 1 ms 4956 KB Output is correct
45 Correct 2 ms 4956 KB Output is correct
46 Correct 2 ms 4956 KB Output is correct
47 Correct 1 ms 4956 KB Output is correct
48 Correct 2 ms 4956 KB Output is correct
49 Correct 2 ms 5212 KB Output is correct
50 Correct 1 ms 4952 KB Output is correct
51 Correct 1 ms 4956 KB Output is correct
52 Correct 1 ms 4956 KB Output is correct
53 Correct 2 ms 5212 KB Output is correct
54 Correct 2 ms 5152 KB Output is correct
55 Correct 2 ms 4956 KB Output is correct
56 Correct 1 ms 4956 KB Output is correct
57 Correct 2 ms 4956 KB Output is correct
58 Correct 2 ms 5212 KB Output is correct
59 Runtime error 5 ms 10076 KB Execution killed with signal 11
60 Halted 0 ms 0 KB -