oj.uz

Submission #999953

# Submission time Handle Problem Language Result Execution time Memory
999953 2024-06-16T11:14:12 Z shmax Parachute rings (IOI12_rings) C++17
52 / 100
 4000 ms 137984 KB 
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>

#pragma GCC optimize("O3")
#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 int long long

#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;

DSU dsu2;
int cycle_sz;
int cnt_cyc = 0;

void Init(int32_t N_) {
    n = N_;
//    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]);
        }
        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]++;
    deg_sorted.insert({deg[a], a});
    deg_sorted.insert({deg[b], b});
    if (n != 1 and deg_sorted.rbegin()->first > 3 and prev(prev(deg_sorted.end()))->first > 3) {
        is_zero = true;
    }
    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);
            }
            for (auto x: g[a]) {
                if (have3[x] or deg[x] == 3) continue;
                have3[x] = true;
                neight3.push_back(x);
                auto [f, d] = create(x);
                neightdsues.push_back(d);
                goodneight3.push_back(f);
            }
        }
        if (deg[b] == 3) {
            {
                cnt3++;
                roots3.push_back(b);
                auto [f, d] = create(b);
                dsues.push_back(d);
                goods3.push_back(f);
            }
            for (auto x: g[b]) {
                if (have3[x] or deg[x] == 3) 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;
        };
        set<int> can;
        for (int i = 0; i < len(roots3); i++) {
            if (!goods3[i]) continue;
            if (!check(roots3[i])) continue;
            can.insert(roots3[i]);
        }
        for (int i = 0; i < len(neight3); i++) {
            if (!goodneight3[i]) continue;
            if (!check(neight3[i])) continue;
            can.insert(neight3[i]);
        }
        return len(can);
    }
    int ans = 0;
    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:267:9: warning: unused variable 'ans' [-Wunused-variable]
  267 |     int ans = 0;
      |         ^~~
rings.cpp:274:1: warning: control reaches end of non-void function [-Wreturn-type]
  274 | }
      | ^

Subtask #1
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 5 ms 1020 KB Output is correct
3 Correct 8 ms 984 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 3 ms 604 KB Output is correct
6 Correct 5 ms 940 KB Output is correct
7 Correct 2 ms 1112 KB Output is correct
8 Correct 3 ms 860 KB Output is correct
9 Correct 6 ms 944 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 1249 ms 57428 KB Output is correct
2 Correct 3189 ms 103648 KB Output is correct
3 Correct 413 ms 137984 KB Output is correct
4 Execution timed out 4053 ms 109924 KB Time limit exceeded
5 Halted 0 ms 0 KB -

Subtask #3
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 5 ms 1020 KB Output is correct
3 Correct 8 ms 984 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 3 ms 604 KB Output is correct
6 Correct 5 ms 940 KB Output is correct
7 Correct 2 ms 1112 KB Output is correct
8 Correct 3 ms 860 KB Output is correct
9 Correct 6 ms 944 KB Output is correct
10 Correct 6 ms 1116 KB Output is correct
11 Correct 5 ms 1116 KB Output is correct
12 Correct 13 ms 2336 KB Output is correct
13 Correct 11 ms 1884 KB Output is correct
14 Correct 7 ms 1648 KB Output is correct
15 Correct 9 ms 2396 KB Output is correct
16 Correct 9 ms 1356 KB Output is correct
17 Correct 4 ms 2140 KB Output is correct
18 Correct 7 ms 3752 KB Output is correct
19 Correct 10 ms 1372 KB Output is correct
20 Correct 13 ms 1724 KB Output is correct

Subtask #4
14.0 / 14.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 5 ms 1020 KB Output is correct
3 Correct 8 ms 984 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 3 ms 604 KB Output is correct
6 Correct 5 ms 940 KB Output is correct
7 Correct 2 ms 1112 KB Output is correct
8 Correct 3 ms 860 KB Output is correct
9 Correct 6 ms 944 KB Output is correct
10 Correct 6 ms 1116 KB Output is correct
11 Correct 5 ms 1116 KB Output is correct
12 Correct 13 ms 2336 KB Output is correct
13 Correct 11 ms 1884 KB Output is correct
14 Correct 7 ms 1648 KB Output is correct
15 Correct 9 ms 2396 KB Output is correct
16 Correct 9 ms 1356 KB Output is correct
17 Correct 4 ms 2140 KB Output is correct
18 Correct 7 ms 3752 KB Output is correct
19 Correct 10 ms 1372 KB Output is correct
20 Correct 13 ms 1724 KB Output is correct
21 Correct 42 ms 5204 KB Output is correct
22 Correct 67 ms 8272 KB Output is correct
23 Correct 92 ms 10324 KB Output is correct
24 Correct 102 ms 11048 KB Output is correct
25 Correct 43 ms 11080 KB Output is correct
26 Correct 102 ms 11884 KB Output is correct
27 Correct 105 ms 9296 KB Output is correct
28 Correct 34 ms 15000 KB Output is correct
29 Correct 38 ms 17212 KB Output is correct
30 Correct 174 ms 11092 KB Output is correct

Subtask #5
0 / 31.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 5 ms 1020 KB Output is correct
3 Correct 8 ms 984 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 3 ms 604 KB Output is correct
6 Correct 5 ms 940 KB Output is correct
7 Correct 2 ms 1112 KB Output is correct
8 Correct 3 ms 860 KB Output is correct
9 Correct 6 ms 944 KB Output is correct
10 Correct 6 ms 1116 KB Output is correct
11 Correct 1249 ms 57428 KB Output is correct
12 Correct 3189 ms 103648 KB Output is correct
13 Correct 413 ms 137984 KB Output is correct
14 Execution timed out 4053 ms 109924 KB Time limit exceeded
15 Halted 0 ms 0 KB -