oj.uz

Submission #794166

# Submission time Handle Problem Language Result Execution time Memory
794166 2023-07-26T10:10:46 Z PixelCat Sorting (IOI15_sorting) C++14
74 / 100
 1000 ms 266256 KB 
#ifdef NYAOWO
#include "grader.cpp"
#endif

#include "sorting.h"

#include <bits/stdc++.h>
#define For(i, a, b) for(int i = a; i <= b; i++)
#define Forr(i, a, b) for(int i = a; i >= b; i--)
#define F first
#define S second
#define all(x) x.begin(), x.end()
#define sz(x) ((int)x.size())
#define eb emplace_back
#define int LL
using namespace std;
using LL = long long;
using pii = pair<int, int>;

const int MAXN = 200'000;
const int MAXM = 3 * MAXN;

struct DSU {
    int p[MAXN + 10];
    int sz[MAXN + 10];
    int blk;
    vector<pii> hist;
    void init(int n) {
        // cerr << "dsu init!\n";
        memset(p, -1, sizeof(p));
        memset(sz, 0, sizeof(sz));
        blk = n;
        hist.clear();
    }
    int find(int n) {
        if(p[n] < 0) return n;
        return find(p[n]);
    }
    void uni(int a, int b) {
        // cerr << "dsu uni " << a << " " << b << "\n";
        a = find(a); b = find(b);
        if(a == b) {
            hist.eb(-1, -1);
            return;
        }
        if(sz[a] < sz[b]) swap(a, b);
        p[b] = a;
        sz[a] += sz[b] + 1;
        blk--;
        hist.eb(a, b);
    }
    void undo() {
        int a, b;
        tie(a, b) = hist.back();
        hist.pop_back();
        if(a < 0) return;
        p[b] = -1;
        sz[a] -= sz[b] + 1;
        blk++;
    }
} dsu;

#define L(id) ((id) * 2 + 1)
#define R(id) ((id) * 2 + 2)
struct SegTree {
    vector<pii> ops[MAXM * 4 + 10];
    int ans;
    void init(int m) {
        ans = m + 1;
        For(i, 0, MAXM * 4 + 10 - 1) {
            ops[i].clear();
        }
    }
    void add(int id, int l, int r, int L, int R, pii p) {
        if(l > R || r < L) return;
        if(l >= L && r <= R) {
            ops[id].eb(p);
            return;
        }
        int m = (l + r) / 2;
        if(L <= m) add(L(id), l, m, L, R, p);
        if(R > m)  add(R(id), m + 1, r, L, R, p);
    }
    void traverse(int id, int l, int r, int N) {
        // cerr << "ops: " << id << " - " << sz(ops[id]) << "\n";
        for(auto &p:ops[id]) dsu.uni(p.F, p.S);
        if(l == r) {
            if(N - dsu.blk <= l) ans = min(ans, l);
            // cerr << "traverse: " << l << " " << dsu.blk << "\n";
        } else {
            int m = (l + r) / 2;
            traverse(L(id), l, m, N);
            traverse(R(id), m + 1, r, N);
        }
        For(_, 1, sz(ops[id])) dsu.undo();
    }
} seg;

int val[MAXN + 10];
int pos[MAXN + 10];
int last[MAXN + 10];

int tmp[MAXN + 10];
bool check(int n, int lim, vector<pii> &ops) {
    For(i, 0, n - 1) tmp[i] = val[i];
    ops.clear();
    For(i, 0, n - 1) {
        while(tmp[i] != i) {
            ops.eb(tmp[i], tmp[tmp[i]]);
            swap(tmp[i], tmp[tmp[i]]);
        }
    }
    return sz(ops) <= lim;
}

int32_t findSwapPairs2(int32_t N, int32_t S[], int32_t M, int32_t X[], int32_t Y[]) {
    bool pote = true;
    For(i, 0, N - 1) {
        val[i] = S[i];
        pos[val[i]] = i;
        if(S[i] != i) pote = false;
    }
    if(pote) return 0;
    For(i, 0, M - 1) {
        int p1 = X[i], p2 = Y[i];
        swap(pos[val[p1]], pos[val[p2]]);
        swap(val[p1], val[p2]);
        vector<pii> op;
        if(check(N, i + 1, op)) {
            return (int32_t)(i + 1);
        }
    }
    assert(false);
    return 0;
}

int32_t findSwapPairs(int32_t N, int32_t S[], int32_t M, int32_t X[], int32_t Y[], int32_t P[], int32_t Q[]) {
    For(i, 0, N - 1) {
        val[i] = S[i];
        pos[val[i]] = i;
    }

    // add edges to segment tree
    seg.init(M);
    memset(last, -1, sizeof(last));
    For(i, 0, M - 1) {
        int p1 = X[i], p2 = Y[i];
        seg.add(0, 0, M, last[p1] + 1, i, pii(p1, val[p1]));
        seg.add(0, 0, M, last[p2] + 1, i, pii(p2, val[p2]));
        last[p1] = i; last[p2] = i;
        swap(pos[val[p1]], pos[val[p2]]);
        swap(val[p1], val[p2]);
    }
    For(i, 0, N - 1) {
        seg.add(0, 0, M, last[i] + 1, M, pii(i, val[i]));
    }

    // traverse through segment tree
    dsu.init(N);
    seg.traverse(0, 0, M, N);
    
    // restore states at time i
    For(i, 0, N - 1) {
        val[i] = S[i];
        pos[val[i]] = i;
    }
    For(i, 0, seg.ans - 1) {
        int p1 = X[i], p2 = Y[i];
        swap(pos[val[p1]], pos[val[p2]]);
        swap(val[p1], val[p2]);
    }

    // int ans2 = findSwapPairs2(N, S, M, X, Y);
    // cerr << seg.ans << " " << ans2 << "\n" << flush;
    // assert(seg.ans == ans2);

    // construct answer
    vector<pii> op;
    assert(check(N, seg.ans, op));
    For(j, sz(op), seg.ans - 1) P[j] = Q[j] = 0;
    Forr(j, seg.ans - 1, 0) {
        if(j < sz(op)) {
            int v1 = op[j].F;
            int v2 = op[j].S;
            P[j] = (int32_t)pos[v1];
            Q[j] = (int32_t)pos[v2];
            swap(val[pos[v1]], val[pos[v2]]);
            swap(pos[v1], pos[v2]);
        }
        int p1 = X[j];
        int p2 = Y[j];
        swap(pos[val[p1]], pos[val[p2]]);
        swap(val[p1], val[p2]);
    }
    return (int32_t)(seg.ans);
}

/*

30421
10423
10243

*/

Subtask #1
8.0 / 8.0

# Verdict Execution time Memory Grader output
1 Correct 31 ms 61296 KB Output is correct
2 Correct 31 ms 61268 KB Output is correct
3 Correct 32 ms 61296 KB Output is correct
4 Correct 34 ms 61268 KB Output is correct
5 Correct 32 ms 61320 KB Output is correct
6 Correct 32 ms 61268 KB Output is correct
7 Correct 33 ms 61280 KB Output is correct

Subtask #2
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 31 ms 61296 KB Output is correct
2 Correct 31 ms 61268 KB Output is correct
3 Correct 32 ms 61296 KB Output is correct
4 Correct 34 ms 61268 KB Output is correct
5 Correct 32 ms 61320 KB Output is correct
6 Correct 32 ms 61268 KB Output is correct
7 Correct 33 ms 61280 KB Output is correct
8 Correct 32 ms 61324 KB Output is correct
9 Correct 39 ms 61292 KB Output is correct
10 Correct 33 ms 61532 KB Output is correct
11 Correct 33 ms 61524 KB Output is correct
12 Correct 34 ms 61524 KB Output is correct

Subtask #3
16.0 / 16.0

# Verdict Execution time Memory Grader output
1 Correct 33 ms 61260 KB Output is correct
2 Correct 33 ms 61304 KB Output is correct
3 Correct 33 ms 61524 KB Output is correct
4 Correct 35 ms 61524 KB Output is correct
5 Correct 35 ms 61516 KB Output is correct
6 Correct 33 ms 61356 KB Output is correct

Subtask #4
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 31 ms 61296 KB Output is correct
2 Correct 31 ms 61268 KB Output is correct
3 Correct 32 ms 61296 KB Output is correct
4 Correct 34 ms 61268 KB Output is correct
5 Correct 32 ms 61320 KB Output is correct
6 Correct 32 ms 61268 KB Output is correct
7 Correct 33 ms 61280 KB Output is correct
8 Correct 32 ms 61324 KB Output is correct
9 Correct 39 ms 61292 KB Output is correct
10 Correct 33 ms 61532 KB Output is correct
11 Correct 33 ms 61524 KB Output is correct
12 Correct 34 ms 61524 KB Output is correct
13 Correct 33 ms 61260 KB Output is correct
14 Correct 33 ms 61304 KB Output is correct
15 Correct 33 ms 61524 KB Output is correct
16 Correct 35 ms 61524 KB Output is correct
17 Correct 35 ms 61516 KB Output is correct
18 Correct 33 ms 61356 KB Output is correct
19 Correct 33 ms 61360 KB Output is correct
20 Correct 33 ms 61296 KB Output is correct
21 Correct 50 ms 65764 KB Output is correct
22 Correct 50 ms 65740 KB Output is correct
23 Correct 51 ms 65812 KB Output is correct
24 Correct 49 ms 65420 KB Output is correct
25 Correct 47 ms 65848 KB Output is correct
26 Correct 51 ms 65720 KB Output is correct
27 Correct 49 ms 65776 KB Output is correct

Subtask #5
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 38 ms 63004 KB Output is correct
2 Correct 36 ms 62140 KB Output is correct
3 Correct 41 ms 63956 KB Output is correct
4 Correct 44 ms 64032 KB Output is correct
5 Correct 42 ms 64052 KB Output is correct
6 Correct 48 ms 64016 KB Output is correct
7 Correct 44 ms 64088 KB Output is correct
8 Correct 42 ms 63948 KB Output is correct
9 Correct 48 ms 64068 KB Output is correct
10 Correct 42 ms 64072 KB Output is correct
11 Correct 42 ms 63848 KB Output is correct
12 Correct 41 ms 64072 KB Output is correct
13 Correct 43 ms 64060 KB Output is correct
14 Correct 36 ms 61968 KB Output is correct

Subtask #6
0 / 26.0

# Verdict Execution time Memory Grader output
1 Correct 38 ms 63004 KB Output is correct
2 Correct 36 ms 62140 KB Output is correct
3 Correct 41 ms 63956 KB Output is correct
4 Correct 44 ms 64032 KB Output is correct
5 Correct 42 ms 64052 KB Output is correct
6 Correct 48 ms 64016 KB Output is correct
7 Correct 44 ms 64088 KB Output is correct
8 Correct 42 ms 63948 KB Output is correct
9 Correct 48 ms 64068 KB Output is correct
10 Correct 42 ms 64072 KB Output is correct
11 Correct 42 ms 63848 KB Output is correct
12 Correct 41 ms 64072 KB Output is correct
13 Correct 43 ms 64060 KB Output is correct
14 Correct 36 ms 61968 KB Output is correct
15 Correct 523 ms 149856 KB Output is correct
16 Execution timed out 1010 ms 266256 KB Time limit exceeded
17 Halted 0 ms 0 KB -