oj.uz

Submission #409550

# Submission time Handle Problem Language Result Execution time Memory
409550 2021-05-21T04:32:03 Z rrrr10000 Mousetrap (CEOI17_mousetrap) C++14
100 / 100
 1192 ms 235668 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(){
    cin.tie(0);ios::sync_with_stdio(false);
    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=n*2,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:81:9: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
   81 |         for(ll x:al)num.pb(g[x].size()-2);num.back()++;
      |         ^~~
mousetrap.cpp:81:43: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
   81 |         for(ll x:al)num.pb(g[x].size()-2);num.back()++;
      |                                           ^~~
mousetrap.cpp:87:51: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   87 |             for(ll x:g[al[i]])if(x!=par[al[i]]&&(i==al.size()-1||x!=al[i+1])){
      |                                                  ~^~~~~~~~~~~~~
mousetrap.cpp:91:19: 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]
   91 |             if(cnt>al.size()-i||cnt>md)able=false;
      |                ~~~^~~~~~~~~~~~

Subtask #1
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 204 KB Output is correct
2 Correct 1 ms 312 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 312 KB Output is correct
6 Correct 1 ms 204 KB Output is correct
7 Correct 1 ms 312 KB Output is correct
8 Correct 1 ms 204 KB Output is correct
9 Correct 1 ms 204 KB Output is correct
10 Correct 1 ms 204 KB Output is correct

Subtask #2
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 437 ms 79832 KB Output is correct
2 Correct 361 ms 71964 KB Output is correct
3 Correct 919 ms 78040 KB Output is correct
4 Correct 415 ms 39900 KB Output is correct
5 Correct 933 ms 78140 KB Output is correct
6 Correct 965 ms 78024 KB Output is correct

Subtask #3
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 204 KB Output is correct
2 Correct 1 ms 312 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 312 KB Output is correct
6 Correct 1 ms 204 KB Output is correct
7 Correct 1 ms 312 KB Output is correct
8 Correct 1 ms 204 KB Output is correct
9 Correct 1 ms 204 KB Output is correct
10 Correct 1 ms 204 KB Output is correct
11 Correct 1 ms 204 KB Output is correct
12 Correct 1 ms 332 KB Output is correct
13 Correct 1 ms 316 KB Output is correct
14 Correct 1 ms 460 KB Output is correct
15 Correct 1 ms 460 KB Output is correct
16 Correct 1 ms 312 KB Output is correct
17 Correct 1 ms 332 KB Output is correct
18 Correct 1 ms 332 KB Output is correct
19 Correct 1 ms 332 KB Output is correct
20 Correct 1 ms 332 KB Output is correct
21 Correct 1 ms 332 KB Output is correct
22 Correct 1 ms 332 KB Output is correct

Subtask #4
35.0 / 35.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 204 KB Output is correct
2 Correct 1 ms 312 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 312 KB Output is correct
6 Correct 1 ms 204 KB Output is correct
7 Correct 1 ms 312 KB Output is correct
8 Correct 1 ms 204 KB Output is correct
9 Correct 1 ms 204 KB Output is correct
10 Correct 1 ms 204 KB Output is correct
11 Correct 437 ms 79832 KB Output is correct
12 Correct 361 ms 71964 KB Output is correct
13 Correct 919 ms 78040 KB Output is correct
14 Correct 415 ms 39900 KB Output is correct
15 Correct 933 ms 78140 KB Output is correct
16 Correct 965 ms 78024 KB Output is correct
17 Correct 1 ms 204 KB Output is correct
18 Correct 1 ms 332 KB Output is correct
19 Correct 1 ms 316 KB Output is correct
20 Correct 1 ms 460 KB Output is correct
21 Correct 1 ms 460 KB Output is correct
22 Correct 1 ms 312 KB Output is correct
23 Correct 1 ms 332 KB Output is correct
24 Correct 1 ms 332 KB Output is correct
25 Correct 1 ms 332 KB Output is correct
26 Correct 1 ms 332 KB Output is correct
27 Correct 1 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 394 ms 82140 KB Output is correct
31 Correct 416 ms 82308 KB Output is correct
32 Correct 1016 ms 235668 KB Output is correct
33 Correct 439 ms 212720 KB Output is correct
34 Correct 959 ms 77984 KB Output is correct
35 Correct 986 ms 77968 KB Output is correct
36 Correct 1192 ms 94800 KB Output is correct
37 Correct 1178 ms 94720 KB Output is correct
38 Correct 912 ms 98992 KB Output is correct
39 Correct 884 ms 99096 KB Output is correct
40 Correct 907 ms 98956 KB Output is correct