Submission #1184393

#	Time	Username	Problem	Language	Result	Execution time	Memory
1184393		sasde	Ball Machine (BOI13_ballmachine)	C++20	68.43 / 100	224 ms	25788 KiB

ballmachine

#include<bits/stdc++.h>
#define str string
#define task "strdel"
#define ii pair<int,int>
#define iii pair<int,ii>
#define iv pair<ii,ii>
#define se second
#define fi first
#define ffi fi.fi
#define sfi se.fi
#define sse se.se
#define fse fi.se
#define lt(i, c, d) for(int i = c; i <= d; ++i)
#define fl(i, c, d) for(int i = d; i >= c; --i)
#define pb push_back
#define emb emplace_back
#define emf emplace_front
#define em emplace
using namespace std;
const int N=1e5+5,lg=20,mod=1e9+7;
mt19937 rd(chrono::steady_clock::now().time_since_epoch().count());
int Rand(int u,int v){
 return u+rd()%(v-u+1);
}
int n,q,goc,sz[N],h[N],zz,up[N][lg+5],minn[N];
vector<int>a[N];
bool k[N];
vector<int>res1;
void dfs1(int u){
    for(int v:a[u]){
        dfs1(v);
    }
    res1.emb(u);
}
void dfs(int u){
  minn[u]=u;sz[u]=1;
  for(int v:a[u]){
    h[v]=h[u]+1;
    up[v][0]=u;
    dfs(v);
    minn[u]=min(minn[u],minn[v]);
  }

}
void giai1(int x){
    while(x--){
        k[zz=res1.back()]=1;
        res1.pop_back();
    }
  cout <<zz<<'\n';
}
int laycha(int x,int u){
for(int j=0;j<=lg;++j){
  if(u&(1<<j)){
    x=up[x][j];
  }
}
return x;
}
void giai2(int x){
  int l=1,r=h[x],res=0;
  while(l<=r){
    int mid=(r+l)>>1;
    int u=laycha(x,mid);
    // cout <<u<<" "<<k[u]<<'\n';
    if(!k[u]){
      r=mid-1;
    }
    else{
      l=mid+1;
      res=mid;
    }
  }
  // cout <<res;
  int u=laycha(x,res);
  k[u]=false;
  res1.emb(u);
  cout <<res<<'\n';
}
void solve(){
    cin >> n >> q;
    for(int i=1;i<=n;++i){
        int u;
        cin >> u;
        if(u==0)goc=i;
        else a[u].emb(i);
    }
    dfs(goc);
    for(int j=1;j<=lg;++j)
    for(int i=1;i<=n;++i)up[i][j]=up[up[i][j-1]][j-1];
    for(int i=1;i<=n;++i){
      sort(a[i].begin(),a[i].end(),[](const int &x,const int &y){
        return minn[x]<minn[y];
      });
    }
    dfs1(goc);
    reverse(res1.begin(),res1.end());
    while(q--){
      int t,u;
      cin >> t >> u;
      if(t==1)giai1(u);
      else giai2(u);
    }
}
main()
{
  srand(time(0));
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
    if(fopen(task".inp","r")){
      freopen(task".inp","r",stdin);
      freopen(task".out","w",stdout);
    }
    int t=1;
 //   cin >> t;
while(t--){
    solve();
}

}

Compilation message (stderr)

ballmachine.cpp:105:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
  105 | main()
      | ^~~~
ballmachine.cpp: In function 'int main()':
ballmachine.cpp:112:14: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  112 |       freopen(task".inp","r",stdin);
      |       ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
ballmachine.cpp:113:14: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  113 |       freopen(task".out","w",stdout);
      |       ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 9.6154 / 25
• Subtask 2: 17.1429 / 30
• Subtask 3: 40 / 40
• Subtask 4: 1.6667 / 5