oj.uz

Submission #799217

# Submission time Handle Problem Language Result Execution time Memory
799217 2023-07-31T10:49:49 Z jlallas384 Parachute rings (IOI12_rings) C++17
20 / 100
 4000 ms 168496 KB 
#include <bits/stdc++.h>
using namespace std;



struct ufds{
    vector<int> sz, par;
    ufds(){}
    ufds(int n): sz(n, 1), par(n){
        iota(par.begin(), par.end(), 0);
    }
    int find(int a){
        return par[a] == a ? a : par[a] = find(par[a]);
    }
    int unite(int a, int b){
        a = find(a), b = find(b);
        if(a == b) return 0;
        if(sz[a] < sz[b]) swap(a, b);
        par[b] = a;
        sz[a] += sz[b];
        return 1;
    }
};

set<int> ans;
vector<vector<int>> g, tree;
vector<int> deg;
int n;
ufds ds;

int bad = 0;
int d4 = 0;

void Init(int N){
    n = N;
    g.resize(n);
    tree.resize(n);
    deg.resize(n);
    for(int i = 0; i < n; i++){
        ans.insert(i);
    }
    ds = ufds(n);
}

void proc(int a, int add = 1){
    if(deg[a] == 4){
        if(add){
            d4++;
            if(d4 == 2) bad = 1;
        }
        if(!ans.count(a)) ans = {};
        else ans = {a};
    }else if(deg[a] == 3){
        set<int> nans;
        if(ans.count(a)) nans.insert(a);
        for(int u: g[a]){
            if(ans.count(u)) nans.insert(u);
        }
        ans = nans;
    }
}
int cyc = 0;

vector<int> path;
int dfs(int v, int p, int x){
    path.push_back(v);
    if(v == x) return 1;
    for(int u: tree[v]) if(u != p){
        if(dfs(u, v, x)) return 1;
    }
    path.pop_back();
    return 0;
}

int dfs2(int v, vector<int> &vis, int p){
    vis[v] = 2;
    for(int u: g[v]){
        if(!vis[u]){
            if(dfs2(u, vis, v)) return 1;
        }
        else if(vis[u] == 2 && u != p){
            return 1;
        }
    }
    return 0;
}
int cancer = -1;
int CountCritical(){    
    if(bad) return 0;
    if(ans.size() == 0) return 0;
    int tot = 0;
    if(cyc){
        set<int> gds;
        int cnts = 0;
        for(int i = 0; i < n; i++){
            cnts += deg[i] >= 3;
        }
        for(int v = 0; v < n; v++){
            vector<int> vis(n);
            vis[v] = 1;
            int ok = 1;
            int t = cnts - (deg[v] >= 3);
            for(int u: g[v]){
                t -= (deg[u] == 3);
            }
            for(int i = 0; i < n; i++){
                if(!vis[i] && dfs2(i, vis, -1)){
                    ok = 0;
                }
            }
            ok &= (t == 0);
            tot += ok;
            if(ok) gds.insert(v);
        }
        if(tot == 0) bad = 1;
        cancer = tot;
        assert(gds == ans);
        assert(tot == ans.size());
    }
    if(bad) return 0;
    else if(!cyc) return ans.size();
    return tot;
}






void Link(int a, int b){
    if(bad) return;
    int res = ds.unite(a, b);
    deg[a]++, deg[b]++;
    g[a].push_back(b);
    g[b].push_back(a);
    proc(a), proc(b);
    if(!res){
        if(!cyc){
            dfs(a, -1, b);
            ans = {};
            for(int x: path){
                ans.insert(x);
            }
            for(int i = 0; i < n; i++){
                proc(i);
            }
            set<int> gds;
            int cnts = 0;
            for(int i = 0; i < n; i++){
                cnts += deg[i] >= 3;
            }
            int tot = 0;
            for(int v = 0; v < n; v++){
                vector<int> vis(n);
                vis[v] = 1;
                int ok = 1;
                int t = cnts - (deg[v] >= 3);
                for(int u: g[v]){
                    t -= (deg[u] == 3);
                }
                for(int i = 0; i < n; i++){
                    if(!vis[i] && dfs2(i, vis, -1)){
                        ok = 0;
                    }
                }
                ok &= (t == 0);
                tot += ok;
                if(ok) gds.insert(v);
            }
            if(tot == 0) bad = 1;
            cancer = tot;
            assert(gds == ans);
            assert(tot == ans.size());
            cyc = 1;
        }else{
            if(ans.size() > 2) bad = 1;
            return;
        }
    }else{
        tree[a].push_back(b);
        tree[b].push_back(a);
    }
}

Compilation message

In file included from /usr/include/c++/10/cassert:44,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:33,
                 from rings.cpp:1:
rings.cpp: In function 'int CountCritical()':
rings.cpp:118:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::set<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  118 |         assert(tot == ans.size());
      |                ~~~~^~~~~~~~~~~~~
rings.cpp: In function 'void Link(int, int)':
rings.cpp:173:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::set<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  173 |             assert(tot == ans.size());
      |                    ~~~~^~~~~~~~~~~~~

Subtask #1
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 2 ms 852 KB Output is correct
3 Correct 3 ms 980 KB Output is correct
4 Correct 23 ms 480 KB Output is correct
5 Correct 269 ms 932 KB Output is correct
6 Correct 1108 ms 1592 KB Output is correct
7 Correct 1 ms 852 KB Output is correct
8 Correct 242 ms 1008 KB Output is correct
9 Correct 3 ms 1108 KB Output is correct
10 Correct 3 ms 1108 KB Output is correct

Subtask #2
0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 487 ms 87760 KB Output is correct
2 Correct 1033 ms 112732 KB Output is correct
3 Correct 390 ms 106832 KB Output is correct
4 Execution timed out 4083 ms 168496 KB Time limit exceeded
5 Halted 0 ms 0 KB -

Subtask #3
0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 2 ms 852 KB Output is correct
3 Correct 3 ms 980 KB Output is correct
4 Correct 23 ms 480 KB Output is correct
5 Correct 269 ms 932 KB Output is correct
6 Correct 1108 ms 1592 KB Output is correct
7 Correct 1 ms 852 KB Output is correct
8 Correct 242 ms 1008 KB Output is correct
9 Correct 3 ms 1108 KB Output is correct
10 Correct 3 ms 1108 KB Output is correct
11 Incorrect 2887 ms 1108 KB Output isn't correct
12 Halted 0 ms 0 KB -

Subtask #4
0 / 14.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 2 ms 852 KB Output is correct
3 Correct 3 ms 980 KB Output is correct
4 Correct 23 ms 480 KB Output is correct
5 Correct 269 ms 932 KB Output is correct
6 Correct 1108 ms 1592 KB Output is correct
7 Correct 1 ms 852 KB Output is correct
8 Correct 242 ms 1008 KB Output is correct
9 Correct 3 ms 1108 KB Output is correct
10 Correct 3 ms 1108 KB Output is correct
11 Incorrect 2887 ms 1108 KB Output isn't correct
12 Halted 0 ms 0 KB -

Subtask #5
0 / 31.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 2 ms 852 KB Output is correct
3 Correct 3 ms 980 KB Output is correct
4 Correct 23 ms 480 KB Output is correct
5 Correct 269 ms 932 KB Output is correct
6 Correct 1108 ms 1592 KB Output is correct
7 Correct 1 ms 852 KB Output is correct
8 Correct 242 ms 1008 KB Output is correct
9 Correct 3 ms 1108 KB Output is correct
10 Correct 3 ms 1108 KB Output is correct
11 Correct 487 ms 87760 KB Output is correct
12 Correct 1033 ms 112732 KB Output is correct
13 Correct 390 ms 106832 KB Output is correct
14 Execution timed out 4083 ms 168496 KB Time limit exceeded
15 Halted 0 ms 0 KB -