oj.uz

답안 #409547

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
409547 2021-05-21T04:30:16 Z rrrr10000 Mousetrap (CEOI17_mousetrap) C++14
100 / 100
 1766 ms 249092 KB 
#include <bits/stdc++.h>
using namespace std;
#define rep(i, n)  for(long long i=0;i<(long long)(n);i++)
#define REP(i,k,n) for(long long i=k;i<(long long)(n);i++)
#define pb emplace_back
#define lb(v,k) (lower_bound(all(v),(k))-v.begin())
#define ub(v,k) (upper_bound(all(v),(k))-v.begin())
#define fi first
#define se second
#define pi M_PI
#define PQ(T) priority_queue<T>
#define SPQ(T) priority_queue<T,vector<T>,greater<T>>
#define dame(a) {out(a);return 0;}
#define decimal cout<<fixed<<setprecision(15);
#define all(a) a.begin(),a.end()
#define rsort(a) {sort(all(a));reverse(all(a));}
#define dupli(a) {sort(all(a));a.erase(unique(all(a)),a.end());}
typedef long long ll;
typedef pair<ll,ll> P;
typedef tuple<ll,ll,ll> PP;
typedef tuple<ll,ll,ll,ll> PPP;
using vi=vector<ll>;
using vvi=vector<vi>;
using vvvi=vector<vvi>;
using vvvvi=vector<vvvi>;
using vp=vector<P>;
using vvp=vector<vp>;
using vb=vector<bool>;
using vvb=vector<vb>;
const ll inf=1001001001001001001;
const ll INF=1001001001;
const ll mod=1000000007;
const double eps=1e-10;
template<class T> bool chmin(T&a,T b){if(a>b){a=b;return true;}return false;}
template<class T> bool chmax(T&a,T b){if(a<b){a=b;return true;}return false;}
template<class T> void out(T a){cout<<a<<'\n';}
template<class T> void outp(T a){cout<<'('<<a.fi<<','<<a.se<<')'<<'\n';}
template<class T> void outvp(T v){rep(i,v.size())cout<<'('<<v[i].fi<<','<<v[i].se<<')';cout<<'\n';}
template<class T> void outvvp(T v){rep(i,v.size())outvp(v[i]);}
template<class T> void outv(T v){rep(i,v.size()){if(i)cout<<' ';cout<<v[i];}cout<<'\n';}
template<class T> void outvv(T v){rep(i,v.size())outv(v[i]);}
template<class T> bool isin(T x,T l,T r){return (l)<=(x)&&(x)<=(r);}
template<class T> void yesno(T b){if(b)out("yes");else out("no");}
template<class T> void YesNo(T b){if(b)out("Yes");else out("No");}
template<class T> void YESNO(T b){if(b)out("YES");else out("NO");}
template<class T> void outset(T s){auto itr=s.begin();while(itr!=s.end()){if(itr!=s.begin())cout<<' ';cout<<*itr;itr++;}cout<<'\n';}
void outs(ll a,ll b){if(a>=inf-100)out(b);else out(a);}
ll gcd(ll a,ll b){if(b==0)return a;return gcd(b,a%b);}
ll modpow(ll a,ll b){ll res=1;a%=mod;while(b){if(b&1)res=res*a%mod;a=a*a%mod;b>>=1;}return res;}

int main(){
    ll n,rt,st;cin>>n>>rt>>st;rt--;st--;
    if(rt==st)dame(0);
    vvi g(n);rep(i,n-1){
        ll a,b;cin>>a>>b;a--;b--;
        g[a].pb(b);g[b].pb(a);
    }
    vi dp(n);
    vi par(n);
    function<void(ll,ll)> dfs=[&](ll i,ll p){
        par[i]=p;
        vi srt;
        for(ll x:g[i])if(x!=p){
            dfs(x,i);
            srt.pb(dp[x]);
        }rsort(srt);
        if(srt.size()>1)dp[i]=srt[1];
        dp[i]+=srt.size();
    };dfs(rt,-1);
    ll ok=INF,ng=-1;
    // outv(dp);
    while(ok-ng>1){
        ll md=(ok+ng)/2;
        ll cnt=0;
        ll cur=st;
        vi num,al;
        while(cur!=rt){
            al.pb(cur);cur=par[cur];
        }reverse(all(al));
        for(ll x:al)num.pb(g[x].size()-2);num.back()++;
        vi rui=num;
        rep(i,rui.size()-1)rui[i+1]+=rui[i];
        bool able=true;
        for(int i=al.size()-1;i>=0;i--){
            ll tmp=0;vi srt;
            for(ll x:g[al[i]])if(x!=par[al[i]]&&(i==al.size()-1||x!=al[i+1])){
                if(cnt+rui[i]+dp[x]>md)tmp++;
            }
            cnt+=tmp;
            if(cnt>al.size()-i||cnt>md)able=false;
        }
        if(able)ok=md;
        else ng=md;
    }
    out(ok);
}

Compilation message

mousetrap.cpp: In function 'int main()':
mousetrap.cpp:80:9: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
   80 |         for(ll x:al)num.pb(g[x].size()-2);num.back()++;
      |         ^~~
mousetrap.cpp:80:43: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
   80 |         for(ll x:al)num.pb(g[x].size()-2);num.back()++;
      |                                           ^~~
mousetrap.cpp:86:51: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   86 |             for(ll x:g[al[i]])if(x!=par[al[i]]&&(i==al.size()-1||x!=al[i+1])){
      |                                                  ~^~~~~~~~~~~~~
mousetrap.cpp:90:19: warning: comparison of integer expressions of different signedness: 'll' {aka 'long long int'} and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   90 |             if(cnt>al.size()-i||cnt>md)able=false;
      |                ~~~^~~~~~~~~~~~

Subtask #1
20.0 / 20.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 204 KB Output is correct
2 Correct 1 ms 204 KB Output is correct
3 Correct 1 ms 204 KB Output is correct
4 Correct 1 ms 204 KB Output is correct
5 Correct 1 ms 204 KB Output is correct
6 Correct 1 ms 204 KB Output is correct
7 Correct 1 ms 204 KB Output is correct
8 Correct 1 ms 296 KB Output is correct
9 Correct 1 ms 300 KB Output is correct
10 Correct 1 ms 296 KB Output is correct

Subtask #2
25.0 / 25.0

# 결과 실행 시간 메모리 Grader output
1 Correct 874 ms 78544 KB Output is correct
2 Correct 767 ms 70840 KB Output is correct
3 Correct 1383 ms 76984 KB Output is correct
4 Correct 641 ms 38604 KB Output is correct
5 Correct 1350 ms 76944 KB Output is correct
6 Correct 1365 ms 76848 KB Output is correct

Subtask #3
20.0 / 20.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 204 KB Output is correct
2 Correct 1 ms 204 KB Output is correct
3 Correct 1 ms 204 KB Output is correct
4 Correct 1 ms 204 KB Output is correct
5 Correct 1 ms 204 KB Output is correct
6 Correct 1 ms 204 KB Output is correct
7 Correct 1 ms 204 KB Output is correct
8 Correct 1 ms 296 KB Output is correct
9 Correct 1 ms 300 KB Output is correct
10 Correct 1 ms 296 KB Output is correct
11 Correct 1 ms 204 KB Output is correct
12 Correct 2 ms 332 KB Output is correct
13 Correct 1 ms 300 KB Output is correct
14 Correct 2 ms 460 KB Output is correct
15 Correct 2 ms 460 KB Output is correct
16 Correct 2 ms 296 KB Output is correct
17 Correct 2 ms 332 KB Output is correct
18 Correct 2 ms 332 KB Output is correct
19 Correct 2 ms 332 KB Output is correct
20 Correct 2 ms 332 KB Output is correct
21 Correct 2 ms 332 KB Output is correct
22 Correct 1 ms 332 KB Output is correct

Subtask #4
35.0 / 35.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 204 KB Output is correct
2 Correct 1 ms 204 KB Output is correct
3 Correct 1 ms 204 KB Output is correct
4 Correct 1 ms 204 KB Output is correct
5 Correct 1 ms 204 KB Output is correct
6 Correct 1 ms 204 KB Output is correct
7 Correct 1 ms 204 KB Output is correct
8 Correct 1 ms 296 KB Output is correct
9 Correct 1 ms 300 KB Output is correct
10 Correct 1 ms 296 KB Output is correct
11 Correct 874 ms 78544 KB Output is correct
12 Correct 767 ms 70840 KB Output is correct
13 Correct 1383 ms 76984 KB Output is correct
14 Correct 641 ms 38604 KB Output is correct
15 Correct 1350 ms 76944 KB Output is correct
16 Correct 1365 ms 76848 KB Output is correct
17 Correct 1 ms 204 KB Output is correct
18 Correct 2 ms 332 KB Output is correct
19 Correct 1 ms 300 KB Output is correct
20 Correct 2 ms 460 KB Output is correct
21 Correct 2 ms 460 KB Output is correct
22 Correct 2 ms 296 KB Output is correct
23 Correct 2 ms 332 KB Output is correct
24 Correct 2 ms 332 KB Output is correct
25 Correct 2 ms 332 KB Output is correct
26 Correct 2 ms 332 KB Output is correct
27 Correct 2 ms 332 KB Output is correct
28 Correct 1 ms 332 KB Output is correct
29 Correct 1 ms 204 KB Output is correct
30 Correct 877 ms 92024 KB Output is correct
31 Correct 890 ms 91844 KB Output is correct
32 Correct 1754 ms 249092 KB Output is correct
33 Correct 918 ms 225180 KB Output is correct
34 Correct 1410 ms 90032 KB Output is correct
35 Correct 1419 ms 90104 KB Output is correct
36 Correct 1766 ms 106812 KB Output is correct
37 Correct 1729 ms 106924 KB Output is correct
38 Correct 1395 ms 111244 KB Output is correct
39 Correct 1401 ms 111240 KB Output is correct
40 Correct 1410 ms 111136 KB Output is correct