Submission #603121

#	Time	Username	Problem	Language	Result	Execution time	Memory
603121		definitelynotmee	Split the Attractions (IOI19_split)	C++17	40 / 100	206 ms	42616 KiB

split

#include "split.h"
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using pii = pair<int,int>;
using pll = pair<ll,ll>;
template<typename T> using matrix = vector<vector<T>>;
#define ff first
#define ss second
#define all(x) x.begin(), x.end()

vector<int> find_split(int n, int a, int b, int c, vector<int> p, vector<int> q) {
	matrix<int> g(n), tree(n);
    for(int i = 0; i < p.size(); i++)
        g[p[i]].push_back(q[i]), g[q[i]].push_back(p[i]);
    
    vector<int> sub(n), low(n);
    matrix<int> indep(n), dep(n);
    vector<int> pai(n);
    int cen = 0;
    vector<int> tin(n);

    int timer = -1;
    auto dfs =[&](int id, auto dfs)->void{
        sub[id] = 1;
        tin[id] = ++timer;
        low[id] = tin[id];
        int maxi = 0;

        for(int i : g[id]){
            if(sub[i]){
                low[id] = min(low[id],tin[i]);
                continue;
            }
            tree[id].push_back(i);
            tree[i].push_back(id);
            pai[i] = id;
            indep[i].push_back(id);
            
            dfs(i,dfs);
            int cur = sub[i];
            maxi = max(maxi,cur);

            sub[id] += cur;
            if(low[i] < tin[id])
                indep[id].push_back(i);
            else dep[id].push_back(i);
            low[id] = min(low[id],low[i]);
        }
        maxi = max(maxi,n-sub[id]);
        if(maxi <= n/2)
            cen = id;
    };
    dfs(0,dfs);
    sub[pai[cen]] = n-sub[pai[cen]];

    vector<int> v = {a,b,c};
    vector<int> o = {0,1,2};
    sort(all(o),[&](int a, int b){
        return v[a] < v[b];
    });
    vector<int> sz = {v[o[0]],v[o[1]], v[o[2]]};
    array<vector<int>,3> group;
    vector<int> resp(n,2);

    auto filltree =[&](int id, int last, int color, auto dfs)->void{
        group[color].push_back(id);
        resp[id] = color;

        for(int i : g[id]){
            if(i == last)
                continue;
            if(group[color].size() < sz[color])
                dfs(i,id,color,dfs);
        }
    };

    auto fillgraph =[&](int id, int color, auto dfs)->void{
        group[color].push_back(id);
        resp[id] = color;
        for(int i : g[id]){
            if(resp[i] != 2)
                continue;
            if(group[color].size() < sz[color])
                dfs(i,color,dfs);
        }
    };

    auto buildresp =[&](){
        for(int& i : resp)
            i = o[i]+1;
    };

    for(int i : tree[cen]){
        if(sub[i] >= sz[0]){
            filltree(i,cen,0,filltree);
            fillgraph(cen,1,fillgraph);
            buildresp();
            return resp;
        }
    }

    int depsize = 1;
    for(int i : dep[cen])
        depsize+=sub[i];
    if(depsize >= sz[1]){
        if(n-depsize >= sz[0]){
            group[1].push_back(cen);
            resp[cen] = 1;
            for(int i : dep[cen]){
                if(group[1].size() < sz[1])
                    filltree(i,cen,1,filltree);
            }
            fillgraph(indep[cen].back(),0,fillgraph);
            buildresp();
        } else resp = vector<int>(n);
        return resp;
    }
    group[0].push_back(cen);
    resp[cen] = 0;
    for(int i : dep[cen]){
        if(group[0].size() < sz[0])
            filltree(i,cen,0,filltree);
    }
    while(group[0].size() < sz[0]){
        filltree(indep[cen].back(),cen,0,filltree);
    }
    fillgraph(indep[cen].back(),1,fillgraph);
    buildresp();
    
	return resp;
}

Compilation message (stderr)

split.cpp: In function 'std::vector<int> find_split(int, int, int, int, std::vector<int>, std::vector<int>)':
split.cpp:14:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   14 |     for(int i = 0; i < p.size(); i++)
      |                    ~~^~~~~~~~~~
split.cpp:111:36: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and '__gnu_cxx::__alloc_traits<std::allocator<int>, int>::value_type' {aka 'int'} [-Wsign-compare]
  111 |                 if(group[1].size() < sz[1])
split.cpp:122:28: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and '__gnu_cxx::__alloc_traits<std::allocator<int>, int>::value_type' {aka 'int'} [-Wsign-compare]
  122 |         if(group[0].size() < sz[0])
split.cpp:125:27: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and '__gnu_cxx::__alloc_traits<std::allocator<int>, int>::value_type' {aka 'int'} [-Wsign-compare]
  125 |     while(group[0].size() < sz[0]){
split.cpp: In instantiation of 'find_split(int, int, int, int, std::vector<int>, std::vector<int>)::<lambda(int, int, int, auto:24)> [with auto:24 = find_split(int, int, int, int, std::vector<int>, std::vector<int>)::<lambda(int, int, int, auto:24)>]':
split.cpp:96:38:   required from here
split.cpp:73:36: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and '__gnu_cxx::__alloc_traits<std::allocator<int>, int>::value_type' {aka 'int'} [-Wsign-compare]
   73 |             if(group[color].size() < sz[color])
split.cpp: In instantiation of 'find_split(int, int, int, int, std::vector<int>, std::vector<int>)::<lambda(int, int, auto:25)> [with auto:25 = find_split(int, int, int, int, std::vector<int>, std::vector<int>)::<lambda(int, int, auto:25)>]':
split.cpp:97:38:   required from here
split.cpp:84:36: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and '__gnu_cxx::__alloc_traits<std::allocator<int>, int>::value_type' {aka 'int'} [-Wsign-compare]
   84 |             if(group[color].size() < sz[color])

• Subtask 1: 7 / 7
• Subtask 2: 11 / 11
• Subtask 3: 22 / 22
• Subtask 4: 0 / 24
• Subtask 5: 0 / 36