Submission #1020407

#	Time	Username	Problem	Language	Result	Execution time	Memory
1020407		KhoaDuy	Untitled (POI11_rot)	C++14	36 / 100	983 ms	65536 KiB

Main

// Judges with GCC >= 12 only needs Ofast
 #pragma GCC optimize("O3,no-stack-protector,fast-math,unroll-loops,tree-vectorize")
// MLE optimization
 #pragma GCC optimize("conserve-stack")
// Old judges
 #pragma GCC target("sse4.2,popcnt,lzcnt,abm,mmx,fma,bmi,bmi2")
// New judges. Test with assert(__builtin_cpu_supports("avx2"));
// #pragma GCC target("arch=skylake")
// Atcoder
// #pragma GCC target("avx2,popcnt,lzcnt,abm,bmi,bmi2,fma")
#include<bits/stdc++.h>
using namespace std;
#define endl '\n'
const int MAXN=4*1e5;
vector<vector<int>> graph(MAXN+1);
vector<vector<int>> leaf;
int seg[MAXN]={0};
int n;
int ptr=0;
long long ans=0;
void build(int l,int r){
    l+=n,r+=n;
    while(l>1){
        l>>=1,r>>=1;
        for(int v=l;v<=r;v++){
            seg[v]=seg[v<<1]+seg[(v<<1)|1];
        }
    }
}
void modify(int i,int x){
    i+=n;
    seg[i]+=x;
    build(i-n,i-n);
}
long long query(int l,int r){
    if(l>r){
        return 0;
    }
    l+=n,r+=n;
    int curr=0;
    for(;l<=r;l>>=1,r>>=1){
        if(l&1){
            curr+=seg[l];
            l++;
        }
        if(!(r&1)){
            curr+=seg[r];
            r--;
        }
    }
    return curr;
}
void DFS(int u,bool keep){
    if(!graph[u].size()){
        leaf[u].push_back(u);
        if(keep){
            modify(u-1,1);
        }
        return;
    }
    int left=graph[u][0],right=graph[u][1];
    if(leaf[left].size()<leaf[right].size()){
        swap(left,right);
    }
    DFS(right,false);
    DFS(left,true);
    swap(leaf[u],leaf[left]);
    long long tot=leaf[u].size()*leaf[right].size();
    long long inver=0;
    for(int i=0;i<leaf[right].size();i++){
        inver+=query(leaf[right][i],n-1);
    }
    ans+=min(inver,tot-inver);
    if(!keep){
        for(int i=0;i<leaf[u].size();i++){
            modify(leaf[u][i]-1,-1);
        }
    }
    while(!leaf[right].empty()){
        leaf[u].push_back(leaf[right].back());
        if(keep){
            modify(leaf[right].back()-1,1);
        }
        leaf[right].pop_back();
    }
}
vector<int> input;
int tim;
int Buildtree(){
    if(input[ptr]!=0){
        ptr++;
        return input[ptr-1];
    }
    ptr++;
    int u=tim;
    tim++;
    int v=Buildtree();
    graph[u].push_back(v);
    v=Buildtree();
    graph[u].push_back(v);
    return u;
}
 
signed main(){
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cin >> n;
    tim=n+1;
    cin.ignore();
    string line;
    while(getline(cin,line)){
        if(line.empty()){
            break;
        }
        stringstream ss;
        ss << line;
        int x=0;
        ss >> x;
        input.push_back(x);
    }
    int root=Buildtree();
    leaf.resize(tim);
    DFS(root,true);
    cout << ans;
}

Compilation message (stderr)

rot.cpp: In function 'void DFS(int, bool)':
rot.cpp:70:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   70 |     for(int i=0;i<leaf[right].size();i++){
      |                 ~^~~~~~~~~~~~~~~~~~~
rot.cpp:75:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   75 |         for(int i=0;i<leaf[u].size();i++){
      |                     ~^~~~~~~~~~~~~~~

• Subtask 1: 9 / 9
• Subtask 2: 9 / 9
• Subtask 3: 9 / 9
• Subtask 4: 9 / 9
• Subtask 5: 0 / 9
• Subtask 6: 0 / 9
• Subtask 7: 0 / 9
• Subtask 8: 0 / 9
• Subtask 9: 0 / 9
• Subtask 10: 0 / 9
• Subtask 11: 0 / 10