Submission #999974

# Submission time Handle Problem Language Result Execution time Memory
999974 2024-06-16T11:49:35 Z shmax Parachute rings (IOI12_rings) C++17
37 / 100
886 ms 100036 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;
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);
    have3.resize(n);
    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]);
            }
    }
    g[a].push_back(b);
    g[b].push_back(a);
    deg[a]++;
    deg[b]++;
    if (mx1 < deg[a]) {
        if (mx1id != a)
            mx2 = mx1;
        mx1 = deg[a];
        mx1id = a;
    } else if (mx2 < deg[a]) {
        mx2 = deg[a];
    }
    if (mx1 < deg[b]) {
        if (mx1id != b)
            mx2 = mx1;
        mx1 = deg[b];
        mx1id = b;
    } else if (mx2 < deg[b]) {
        mx2 = deg[b];
    }
    if (mx2 > 3) {
        is_zero = true;
        return;
    }
    if (rootb3 == -1 and mx1 > 3) {
        rootb3 = mx1id;
        mx1 = 0;
        mx2 = 0;
        mx1id = -1;
        for (int i = 0; i < n; i++) {
            if (deg[i] > mx1) {
                mx1 = deg[i];
                mx1id = i;
            } else if (mx2 < deg[i]) {
                mx2 = deg[i];
            }
        }
        if (n != 1 and mx2 > 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:310:1: warning: control reaches end of non-void function [-Wreturn-type]
  310 | }
      | ^
# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 2 ms 604 KB Output is correct
3 Correct 1 ms 860 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 1 ms 604 KB Output is correct
6 Correct 1 ms 604 KB Output is correct
7 Correct 1 ms 604 KB Output is correct
8 Correct 1 ms 604 KB Output is correct
9 Correct 2 ms 860 KB Output is correct
10 Correct 2 ms 860 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 182 ms 33008 KB Output is correct
2 Correct 466 ms 66360 KB Output is correct
3 Correct 154 ms 67524 KB Output is correct
4 Correct 523 ms 63060 KB Output is correct
5 Correct 524 ms 73552 KB Output is correct
6 Correct 574 ms 71884 KB Output is correct
7 Correct 158 ms 81000 KB Output is correct
8 Correct 826 ms 91840 KB Output is correct
9 Correct 886 ms 100036 KB Output is correct
10 Correct 339 ms 71248 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 2 ms 604 KB Output is correct
3 Correct 1 ms 860 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 1 ms 604 KB Output is correct
6 Correct 1 ms 604 KB Output is correct
7 Correct 1 ms 604 KB Output is correct
8 Correct 1 ms 604 KB Output is correct
9 Correct 2 ms 860 KB Output is correct
10 Correct 2 ms 860 KB Output is correct
11 Correct 2 ms 856 KB Output is correct
12 Correct 5 ms 1372 KB Output is correct
13 Incorrect 4 ms 1372 KB Output isn't correct
14 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 2 ms 604 KB Output is correct
3 Correct 1 ms 860 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 1 ms 604 KB Output is correct
6 Correct 1 ms 604 KB Output is correct
7 Correct 1 ms 604 KB Output is correct
8 Correct 1 ms 604 KB Output is correct
9 Correct 2 ms 860 KB Output is correct
10 Correct 2 ms 860 KB Output is correct
11 Correct 2 ms 856 KB Output is correct
12 Correct 5 ms 1372 KB Output is correct
13 Incorrect 4 ms 1372 KB Output isn't correct
14 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 2 ms 604 KB Output is correct
3 Correct 1 ms 860 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 1 ms 604 KB Output is correct
6 Correct 1 ms 604 KB Output is correct
7 Correct 1 ms 604 KB Output is correct
8 Correct 1 ms 604 KB Output is correct
9 Correct 2 ms 860 KB Output is correct
10 Correct 2 ms 860 KB Output is correct
11 Correct 182 ms 33008 KB Output is correct
12 Correct 466 ms 66360 KB Output is correct
13 Correct 154 ms 67524 KB Output is correct
14 Correct 523 ms 63060 KB Output is correct
15 Correct 524 ms 73552 KB Output is correct
16 Correct 574 ms 71884 KB Output is correct
17 Correct 158 ms 81000 KB Output is correct
18 Correct 826 ms 91840 KB Output is correct
19 Correct 886 ms 100036 KB Output is correct
20 Correct 339 ms 71248 KB Output is correct
21 Correct 2 ms 856 KB Output is correct
22 Correct 5 ms 1372 KB Output is correct
23 Incorrect 4 ms 1372 KB Output isn't correct
24 Halted 0 ms 0 KB -