oj.uz

Submission #999968

# Submission time Handle Problem Language Result Execution time Memory
999968 2024-06-16T11:41:57 Z shmax Parachute rings (IOI12_rings) C++17
52 / 100
 4000 ms 121284 KB 
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>

#pragma GCC optimize("Ofast")
//#pragma GCC target("avx,avx2,fma")
#pragma GCC optimization ("unroll-loops")
//#pragma GCC target("avx,avx2,sse,sse2,sse3,sse4,popcnt")

using namespace std;
using namespace __gnu_pbds;
#define len(x) (int) x.size()


template<typename T>
using graph = vector<vector<T>>;


template<typename T>
using vec = vector<T>;


struct DSU {
public:
    DSU() : _n(0) {}

    explicit DSU(int n) : _n(n), parent_or_size(n, -1) {}

    int unite(int a, int b) {
        assert(0 <= a && a < _n);
        assert(0 <= b && b < _n);
        int x = leader(a), y = leader(b);
        if (x == y) return x;
        if (-parent_or_size[x] < -parent_or_size[y]) std::swap(x, y);
        parent_or_size[x] += parent_or_size[y];
        parent_or_size[y] = x;
        return x;
    }

    bool one(int a, int b) {
        assert(0 <= a && a < _n);
        assert(0 <= b && b < _n);
        return leader(a) == leader(b);
    }

    int leader(int a) {
        assert(0 <= a && a < _n);
        if (parent_or_size[a] < 0) return a;
        return parent_or_size[a] = leader(parent_or_size[a]);
    }

    int size(int a) {
        assert(0 <= a && a < _n);
        return -parent_or_size[leader(a)];
    }

    std::vector<std::vector<int>> groups() {
        std::vector<int> leader_buf(_n), group_size(_n);
        for (int i = 0; i < _n; i++) {
            leader_buf[i] = leader(i);
            group_size[leader_buf[i]]++;
        }
        std::vector<std::vector<int>> result(_n);
        for (int i = 0; i < _n; i++) {
            result[i].reserve(group_size[i]);
        }
        for (int i = 0; i < _n; i++) {
            result[leader_buf[i]].push_back(i);
        }
        result.erase(
                std::remove_if(result.begin(), result.end(),
                               [&](const std::vector<int> &v) { return v.empty(); }),
                result.end());
        return result;
    }

private:
    int _n;
    // root node: -1 * component size
    // otherwise: parent
    std::vector<int> parent_or_size;
};

int n;
graph<int> g;
DSU dsu;
bool is_zero = false;
vec<int> deg;
set<pair<int, int>> deg_sorted;
int rootb3 = -1;
int cnt3 = 0;
vec<int> roots3;
vec<bool> goods3;
vec<int> neight3;
vec<int> goodneight3;
vec<DSU> dsues;
vec<DSU> neightdsues;
vec<bool> have3;
vec<bool> have;
DSU dsu2;
int cycle_sz;
int cnt_cyc = 0;
int mx1 = 0;
int mx2 = 0;
int mx1id = -1;

void Init(int32_t N_) {
    n = N_;
    have.resize(n, false);
//    dsu = DSU(n);
    g.resize(n);
    deg.resize(n);
    deg_sorted.clear();
    have3.resize(n);
    for (int i = 0; i < n; i++) {
        deg_sorted.insert({0, i});
    }
    dsu2 = DSU(n);
}

pair<bool, DSU> create(int v) {
    DSU d = DSU(n);
    for (int i = 0; i < n; i++) {
        if (i == v) continue;
        for (auto &j: g[i]) {
            if (j == v) continue;
            if (i < j) continue;
            if (d.one(i, j)) {
                return {false, d};
            }
            d.unite(i, j);
        }
    }
    return {true, d};
}

bool add(DSU &d, int a, int b, int v) {
    if (a == v or b == v) return true;
    if (d.one(a, b)) return false;
    d.unite(a, b);
    return true;
}


void Link(int32_t a, int32_t b) {
    if (is_zero)return;
    if (rootb3 != -1) {
        if (!add(dsu, a, b, rootb3)) {
            is_zero = true;
            return;
        }
    } else {
        for (int i = 0; i < len(roots3); i++) {
            if (!goods3[i]) continue;
            goods3[i] = add(dsues[i], a, b, roots3[i]);
        }
        if (cnt3 < 3)
            for (int i = 0; i < len(neight3); i++) {
                if (!goodneight3[i]) continue;
                goodneight3[i] = add(neightdsues[i], a, b, neight3[i]);
            }
    }
    deg_sorted.erase({deg[a], a});
    deg_sorted.erase({deg[b], b});
    g[a].push_back(b);
    g[b].push_back(a);
    deg[a]++;
    deg[b]++;
    if (mx1 < deg[a]) {
        mx2 = mx1;
        mx1 = deg[a];
        mx1id = a;
    } else if (mx2 < deg[a]) {
        mx2 = deg[a];
    }
    if (mx1 < deg[b]) {
        mx2 = mx1;
        mx1 = deg[b];
        mx1id = b;
    } else if (mx2 < deg[b]) {
        mx2 = deg[b];
    }
    deg_sorted.insert({deg[a], a});
    deg_sorted.insert({deg[b], b});
    if (prev(prev(deg_sorted.end()))->first > 3) {
        is_zero = true;
        return;
    }
    if (rootb3 == -1 and deg_sorted.rbegin()->first > 3) {
        rootb3 = deg_sorted.rbegin()->second;
        for (auto &i: g[rootb3]) {
            deg_sorted.erase({deg[i], i});
            deg[i]--;
            deg_sorted.insert({deg[i], i});
        }
        if (n != 1 and prev(prev(deg_sorted.end()))->first > 2)
            is_zero = true;
        auto [f, d] = create(rootb3);
        dsu = d;
        if (!f) {
            is_zero = true;
            return;
        }
    }
    if (rootb3 == -1) {
        if (deg[a] == 3) {
            {
                cnt3++;
                roots3.push_back(a);
                auto [f, d] = create(a);
                dsues.push_back(d);
                goods3.push_back(f);
            }
        }
        auto check = [&](int v) {
            int t = 0;
            for (auto u: g[v])
                t += (deg[u] == 3);
            return t + (deg[v] == 3) == cnt3;
        };
        if (deg[b] == 3) {
            {
                cnt3++;
                roots3.push_back(b);
                auto [f, d] = create(b);
                dsues.push_back(d);
                goods3.push_back(f);
            }
            if (cnt3 < 3) {
                for (auto x: g[b]) {
                    if (have3[x] or deg[x] == 3) continue;
                    if (!check(x)) continue;
                    have3[x] = true;
                    neight3.push_back(x);
                    auto [f, d] = create(x);
                    neightdsues.push_back(d);
                    goodneight3.push_back(f);
                }
            }
        }
        if (deg[a] == 3) {
            if (cnt3 < 3) {
                for (auto x: g[a]) {
                    if (have3[x] or deg[x] == 3) continue;
                    if (!check(x)) continue;
                    have3[x] = true;
                    neight3.push_back(x);
                    auto [f, d] = create(x);
                    neightdsues.push_back(d);
                    goodneight3.push_back(f);
                }
            }
        }
        if (cnt3 > 4) {
            is_zero = true;
            return;
        }

    }
    if (roots3.empty() and rootb3 == -1) {
        if (dsu2.one(a, b)) {
            cnt_cyc++;
            cycle_sz = dsu2.size(a);
        } else {
            dsu2.unite(a, b);
        }
        if (cnt_cyc > 1) {
            is_zero = true;
        }
    }
}


int32_t CountCritical() {
    if (is_zero) return 0;
    if (n == 1) return 1;
    if (rootb3 != -1) {
        return 1;
    }
    if (!roots3.empty()) {
        auto check = [&](int v) {
            int t = 0;
            for (auto u: g[v])
                t += (deg[u] == 3);
            return t + (deg[v] == 3) == cnt3;
        };
        vec<int> can;
        for (int i = 0; i < len(roots3); i++) {
            if (!goods3[i]) continue;
            if (have[roots3[i]]) continue;
            if (!check(roots3[i])) continue;
            have[roots3[i]] = true;
            can.push_back(roots3[i]);
        }
        if (cnt3 < 3)
            for (int i = 0; i < len(neight3); i++) {
                if (!goodneight3[i]) continue;
                if (have[neight3[i]]) continue;
                if (!check(neight3[i])) continue;
                have[roots3[i]] = true;
                can.push_back(neight3[i]);
            }
        for (auto &i: can) {
            have[i] = false;
        }
        return len(can);
    }
    if (cnt_cyc == 1)
        return cycle_sz;
    if (cnt_cyc == 0)
        return n;
}

Compilation message

rings.cpp:6: warning: ignoring '#pragma GCC optimization' [-Wunknown-pragmas]
    6 | #pragma GCC optimization ("unroll-loops")
      | 
rings.cpp: In function 'int32_t CountCritical()':
rings.cpp:311:1: warning: control reaches end of non-void function [-Wreturn-type]
  311 | }
      | ^

Subtask #1
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 4 ms 860 KB Output is correct
3 Correct 5 ms 1116 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 3 ms 604 KB Output is correct
6 Correct 6 ms 856 KB Output is correct
7 Correct 1 ms 860 KB Output is correct
8 Correct 3 ms 800 KB Output is correct
9 Correct 6 ms 1132 KB Output is correct
10 Correct 6 ms 1116 KB Output is correct

Subtask #2
0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 1384 ms 57364 KB Output is correct
2 Correct 3269 ms 103900 KB Output is correct
3 Correct 394 ms 121284 KB Output is correct
4 Execution timed out 4024 ms 117124 KB Time limit exceeded
5 Halted 0 ms 0 KB -

Subtask #3
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 4 ms 860 KB Output is correct
3 Correct 5 ms 1116 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 3 ms 604 KB Output is correct
6 Correct 6 ms 856 KB Output is correct
7 Correct 1 ms 860 KB Output is correct
8 Correct 3 ms 800 KB Output is correct
9 Correct 6 ms 1132 KB Output is correct
10 Correct 6 ms 1116 KB Output is correct
11 Correct 6 ms 1112 KB Output is correct
12 Correct 11 ms 1884 KB Output is correct
13 Correct 10 ms 1884 KB Output is correct
14 Correct 7 ms 1628 KB Output is correct
15 Correct 8 ms 2604 KB Output is correct
16 Correct 9 ms 1628 KB Output is correct
17 Correct 3 ms 1628 KB Output is correct
18 Correct 6 ms 2908 KB Output is correct
19 Correct 11 ms 1628 KB Output is correct
20 Correct 13 ms 1884 KB Output is correct

Subtask #4
14.0 / 14.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 4 ms 860 KB Output is correct
3 Correct 5 ms 1116 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 3 ms 604 KB Output is correct
6 Correct 6 ms 856 KB Output is correct
7 Correct 1 ms 860 KB Output is correct
8 Correct 3 ms 800 KB Output is correct
9 Correct 6 ms 1132 KB Output is correct
10 Correct 6 ms 1116 KB Output is correct
11 Correct 6 ms 1112 KB Output is correct
12 Correct 11 ms 1884 KB Output is correct
13 Correct 10 ms 1884 KB Output is correct
14 Correct 7 ms 1628 KB Output is correct
15 Correct 8 ms 2604 KB Output is correct
16 Correct 9 ms 1628 KB Output is correct
17 Correct 3 ms 1628 KB Output is correct
18 Correct 6 ms 2908 KB Output is correct
19 Correct 11 ms 1628 KB Output is correct
20 Correct 13 ms 1884 KB Output is correct
21 Correct 42 ms 5712 KB Output is correct
22 Correct 84 ms 8788 KB Output is correct
23 Correct 89 ms 10836 KB Output is correct
24 Correct 95 ms 11536 KB Output is correct
25 Correct 30 ms 11080 KB Output is correct
26 Correct 102 ms 12460 KB Output is correct
27 Correct 120 ms 10100 KB Output is correct
28 Correct 31 ms 11728 KB Output is correct
29 Correct 42 ms 13016 KB Output is correct
30 Correct 170 ms 11924 KB Output is correct

Subtask #5
0 / 31.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 4 ms 860 KB Output is correct
3 Correct 5 ms 1116 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 3 ms 604 KB Output is correct
6 Correct 6 ms 856 KB Output is correct
7 Correct 1 ms 860 KB Output is correct
8 Correct 3 ms 800 KB Output is correct
9 Correct 6 ms 1132 KB Output is correct
10 Correct 6 ms 1116 KB Output is correct
11 Correct 1384 ms 57364 KB Output is correct
12 Correct 3269 ms 103900 KB Output is correct
13 Correct 394 ms 121284 KB Output is correct
14 Execution timed out 4024 ms 117124 KB Time limit exceeded
15 Halted 0 ms 0 KB -