oj.uz

Submission #143590

# Submission time Handle Problem Language Result Execution time Memory
143590 2019-08-14T16:54:51 Z VladaMG98 Split the Attractions (IOI19_split) C++17
18 / 100
 124 ms 20068 KB 
#include <bits/stdc++.h>
#include "split.h"
using namespace std;

const int MAXN = 100010;
int subtree_size[MAXN];
vector<int> adj[MAXN];
int parent[MAXN];

void dfs(int src = 0, int prev = -1) {
    //printf("dfs %d %d\n", src, prev);
    subtree_size[src] = 1;
    parent[src] = prev;
    for(auto &xt : adj[src]) {
        if(xt - prev) {
            dfs(xt, src);
            subtree_size[src] += subtree_size[xt];
        }
    }
}

vector<int> get_solution(vector<int> v1, int n1, vector<int> v2, int n2, int n) {
    vector<int> ans(n, 6 - n1 - n2);
    for(auto &x : v1) {
        ans[x] = n1;
    }
    for(auto &x : v2) {
        ans[x] = n2;
    }
    return ans;
}

bool marked[MAXN];
vector<int> extract(int src, int wrong, int sz) {
    marked[wrong] = true;
    vector<int> ans;
    stack<int> nodes;
    nodes.push(src);
    marked[src] = true;
    while((int)ans.size() < sz) {
        int node = nodes.top();
        nodes.pop();
        ans.push_back(node);
        for(auto &x : adj[node]) {
            if(!marked[x]) {
                marked[x] = true;
                nodes.push(x);
            }
        }
    }
    for(auto &x : ans) {
        marked[x] = false;
    }
    marked[wrong] = false;
    return ans;
}

vector<int> blank(int n) {
    vector<int> ans(n, 0);
    return ans;
}

int dsu[MAXN];

void init_set(int x) {
    dsu[x] = x;
}

int get(int x) {
    if(dsu[x] == x) return x;
    return dsu[x] = get(dsu[x]);
}

bool unite(int x, int y) {
    int xr = get(x), yr = get(y);
    if(xr == yr) return false;
    if(rand() % 2) swap(xr, yr);
    dsu[xr] = yr;
    return true;
}

void create_spanning_tree(int n, vector<int> &st_p, vector<int> &st_q, vector<int> p, vector<int> q) {
    for(int i = 0; i < n; i++) {
        init_set(i);
    }
    int m = (int)p.size();
    for(int i = 0; i < m; i++) {
        if(unite(p[i], q[i])) {
            st_p.push_back(p[i]);
            st_q.push_back(q[i]);
        }
    }
    //assert((int)st_p.size() == n - 1);
}

int belongs[MAXN];
set<int> comp_adj[MAXN];
int cnt_nodes[MAXN];

int comp_size;
vector<int> comp_comp;
bool comp_mark[MAXN];
void dfs2(int src) {
    comp_size += cnt_nodes[src];
    comp_mark[src] = true;
    comp_comp.push_back(src);
    for(auto &xt : comp_adj[src]) {
        if(!comp_mark[xt]) {
            dfs2(xt);
        }
    }
}

vector<int> find_split(int n, int a, int b, int c, vector<int> p, vector<int> q) {
    pair<int, int> arr[] = {{a, 1}, {b, 2}, {c, 3}};
    sort(arr, arr + 3);
    int A = arr[0].first, B = arr[1].first, C = arr[2].first;
    vector<int> st_p, st_q;
    create_spanning_tree(n, st_p, st_q, p, q);
    int m = (int)p.size();
    for(int i = 0; i < n - 1; i++) {
        adj[st_p[i]].push_back(st_q[i]);
        adj[st_q[i]].push_back(st_p[i]);
    }
    dfs();
    //for(int i = 0; i < n; i++) {
    //   printf("subtree_size[%d] = %d\n", i, subtree_size[i]);
    //}
    for(int i = 0; i < m; i++) {
        int u = p[i], v = q[i];
        if(subtree_size[u] > subtree_size[v]) swap(u, v);
        int under = subtree_size[u];
        int rest = n - under;
        if(under >= A && rest >= A) {
            //printf("found for edge %d - %d\n", u, v);
            //we've got a solution
            vector<int> set_A, set_B;
            if(under < rest) {
                set_A = extract(u, v, A);
                set_B = extract(v, u, B);
            } else {
                set_A = extract(v, u, A);
                set_B = extract(u, v, B);
            }
            return get_solution(set_A, arr[0].second, set_B, arr[1].second, n);
        }
    }
    //there is no edge connecting two subtrees of sizes >= a
    //meaning that it's a star with all subtrees attached of size < a
    //in tree, there is no such solution
    for(int node = 0; node < n; node++) {
        vector<pair<int, int>> sizes;
        int sm = 0;
        for(auto &xt : adj[node]) {
            if(xt != parent[node]) {
                sizes.push_back({subtree_size[xt], xt});
                sm += subtree_size[xt];
            }
        }
        if(node) {
            sizes.push_back({n - 1 - sm, parent[node]});
        }
        int mx = 0;
        for(auto &pr : sizes) {
            mx = max(mx, pr.second);
        }
        if(mx < A) {
            printf("I am deciding on node %d\n", node);
            for(int i = 0; i < (int)sizes.size(); i++) {
                vector<int> comp_here = extract(sizes[i].second, node, sizes[i].first);
                for(auto &x : comp_here) {
                    belongs[x] = i + 1;
                    marked[x] = false;
                }
                marked[node] = false;
                cnt_nodes[i + 1] = sizes[i].first;
            }
            int new_nodes = (int)sizes.size();
            for(int i = 0; i < m; i++) {
                if(p[i] != node && q[i] != node) {
                    comp_adj[belongs[p[i]]].insert(belongs[q[i]]);
                    comp_adj[belongs[q[i]]].insert(belongs[p[i]]);
                }
            }
            for(int i = 1; i <= new_nodes; i++) {
                if(marked[i]) continue;
                comp_size = 0;
                comp_comp.clear();
                dfs2(i);
                for(auto &x : comp_comp) {
                    comp_mark[x] = false;
                }
                if(comp_size >= A) {
                    //we have a solution
                    int start_node = sizes[i - 1].second;
                    vector<int> ans_A = extract(start_node, node, A);
                    for(auto &x : ans_A) {
                        marked[x] = true;
                    }
                    vector<int> ans_B = extract(node, MAXN - 1, B);
                    return get_solution(ans_A, arr[0].second, ans_B, arr[1].second, n);
                } else {
                    return blank(n);
                }
            }
        }
    }
    assert(false);
}

Compilation message

split.cpp: In function 'std::vector<int> find_split(int, int, int, int, std::vector<int>, std::vector<int>)':
split.cpp:117:45: warning: unused variable 'C' [-Wunused-variable]
     int A = arr[0].first, B = arr[1].first, C = arr[2].first;
                                             ^

Subtask #1
7.0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 7492 KB ok, correct split
2 Correct 8 ms 7416 KB ok, correct split
3 Correct 8 ms 7416 KB ok, correct split
4 Correct 8 ms 7416 KB ok, correct split
5 Correct 8 ms 7416 KB ok, correct split
6 Correct 8 ms 7416 KB ok, correct split
7 Correct 105 ms 19676 KB ok, correct split
8 Correct 99 ms 17500 KB ok, correct split
9 Correct 95 ms 17628 KB ok, correct split
10 Correct 104 ms 19032 KB ok, correct split
11 Correct 104 ms 19036 KB ok, correct split

Subtask #2
11.0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 7416 KB ok, correct split
2 Correct 9 ms 7416 KB ok, correct split
3 Correct 8 ms 7416 KB ok, correct split
4 Correct 112 ms 15316 KB ok, correct split
5 Correct 93 ms 15068 KB ok, correct split
6 Correct 98 ms 18908 KB ok, correct split
7 Correct 105 ms 18020 KB ok, correct split
8 Correct 124 ms 16360 KB ok, correct split
9 Correct 102 ms 14940 KB ok, correct split
10 Correct 80 ms 15704 KB ok, correct split
11 Correct 85 ms 15748 KB ok, correct split
12 Correct 88 ms 15708 KB ok, correct split

Subtask #3
0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 7416 KB ok, correct split
2 Correct 96 ms 15284 KB ok, correct split
3 Correct 37 ms 10292 KB ok, correct split
4 Correct 10 ms 7388 KB ok, correct split
5 Correct 99 ms 16732 KB ok, correct split
6 Correct 98 ms 16604 KB ok, correct split
7 Correct 102 ms 16676 KB ok, correct split
8 Correct 116 ms 17244 KB ok, correct split
9 Correct 103 ms 16364 KB ok, correct split
10 Runtime error 45 ms 20068 KB Execution killed with signal 11 (could be triggered by violating memory limits)
11 Halted 0 ms 0 KB -

Subtask #4
0 / 24.0

# Verdict Execution time Memory Grader output
1 Correct 9 ms 7432 KB ok, correct split
2 Incorrect 10 ms 7416 KB secret mismatch
3 Halted 0 ms 0 KB -

Subtask #5
0 / 36.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 7492 KB ok, correct split
2 Correct 8 ms 7416 KB ok, correct split
3 Correct 8 ms 7416 KB ok, correct split
4 Correct 8 ms 7416 KB ok, correct split
5 Correct 8 ms 7416 KB ok, correct split
6 Correct 8 ms 7416 KB ok, correct split
7 Correct 105 ms 19676 KB ok, correct split
8 Correct 99 ms 17500 KB ok, correct split
9 Correct 95 ms 17628 KB ok, correct split
10 Correct 104 ms 19032 KB ok, correct split
11 Correct 104 ms 19036 KB ok, correct split
12 Correct 8 ms 7416 KB ok, correct split
13 Correct 9 ms 7416 KB ok, correct split
14 Correct 8 ms 7416 KB ok, correct split
15 Correct 112 ms 15316 KB ok, correct split
16 Correct 93 ms 15068 KB ok, correct split
17 Correct 98 ms 18908 KB ok, correct split
18 Correct 105 ms 18020 KB ok, correct split
19 Correct 124 ms 16360 KB ok, correct split
20 Correct 102 ms 14940 KB ok, correct split
21 Correct 80 ms 15704 KB ok, correct split
22 Correct 85 ms 15748 KB ok, correct split
23 Correct 88 ms 15708 KB ok, correct split
24 Correct 8 ms 7416 KB ok, correct split
25 Correct 96 ms 15284 KB ok, correct split
26 Correct 37 ms 10292 KB ok, correct split
27 Correct 10 ms 7388 KB ok, correct split
28 Correct 99 ms 16732 KB ok, correct split
29 Correct 98 ms 16604 KB ok, correct split
30 Correct 102 ms 16676 KB ok, correct split
31 Correct 116 ms 17244 KB ok, correct split
32 Correct 103 ms 16364 KB ok, correct split
33 Runtime error 45 ms 20068 KB Execution killed with signal 11 (could be triggered by violating memory limits)
34 Halted 0 ms 0 KB -