oj.uz

Submission #171840

# Submission time Handle Problem Language Result Execution time Memory
171840 2019-12-30T13:22:00 Z VEGAnn Marriage questions (IZhO14_marriage) C++14
82 / 100
 1500 ms 8164 KB 
#include <bits/stdc++.h>
#pragma GCC optimize("-O3")
#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")
#define sz(x) ((int)x.size())
#define PB push_back
#define MP make_pair
#define y first
#define psh second
#define edge pair<int, bool>
#define pi3 pair<pii, int>
#define MP3(a,b,c) MP(MP(a, b), c)
using namespace std;
const int oo = 1e9;
const int N = 32100;
const int K = 110;
const int PW = 20;

vector<edge> edges;
queue<int> q;
vector<int> g[N];
int ans = 0, s, t, n, m, k, dst[N], ptr[N];

void add_edge(int x, int y){

    g[x].PB(sz(edges));
    edges.PB(edge(y, 0));

    g[y].PB(sz(edges));
    edges.PB(edge(x, 1));

}

bool bad(int l, int r, int v){
    if (v == s || v == t || v < m) return 0;
    return !(m + l <= v && v <= m + r);
}

bool bfs(int l, int r){
    fill(dst, dst + t + 1, oo);

    dst[s] = 0;
    while (sz(q)) q.pop();
    q.push(s);

    while (sz(q)){
        int v = q.front(); q.pop();

        for (int nm : g[v]){
            edge u = edges[nm];
            if (!bad(l, r, u.y) && !u.psh && dst[u.y] > dst[v] + 1){
                dst[u.y] = dst[v] + 1;
                q.push(u.y);
            }
        }
    }

    return (dst[t] < oo);
}

bool dfs(int v, bool pshd){
    if (pshd == 0) return 0;
    if (v == t) return pshd;
    for (; ptr[v] < sz(g[v]); ptr[v]++){
        int nm = g[v][ptr[v]];
        edge u = edges[nm];
        if (dst[u.y] != dst[v] + 1) continue;
        int nw = dfs(u.y, min(pshd, !u.psh));
        if (nw){
            edges[nm].psh = 1;
            edges[nm ^ 1].psh = 0;
            return nw;
        }
    }
    return 0;
}

bool ok(int l, int r){

    if (r - l + 1 < m) return 0;

    int flow = 0;

    for (int i = 0; i < m; i++) {
        int nm = g[s][i];
        flow += edges[nm].psh;
    }

    while (bfs(l, r)){
        fill(ptr, ptr + t + 1, 0);
        int pshd = dfs(s, oo);
        while (pshd > 0){
            flow += pshd;
            pshd = dfs(s, oo);
        }
    }

    return (flow == m);
}

int main(){
    ios_base::sync_with_stdio(0); cin.tie(0);

    cin >> n >> m >> k;

    for (int i = 0; i < k; i++){
        int x, y; cin >> y >> x;
        x--; y--;
        add_edge(x, m + y);
    }

    s = n + m;
    t = n + m + 1;

    for (int i = 0; i < m; i++)
        add_edge(s, i);

    for (int i = 0; i < n; i++)
        add_edge(i + m, t);

    for (int l = 0, r = 0; l < n; l++){

        if (l + m - 1 >= n) break;

        while (r < n && !ok(l, r))
            r++;
        if (r >= n) break;
        ans += n - r;

        int nm = g[t][l];

        if (edges[nm].psh) continue;

        int pr = -1, cr = m + l;
        for (int it = 0; it < sz(g[cr]); it++){
            int nm = g[cr][it];
            edge ed = edges[nm];

            if (ed.y != t && !ed.psh){
                pr = ed.y;
                break;
            }
        }

        nm = g[s][pr];
        edges[nm].psh = 0;
        edges[nm ^ 1].psh = 1;
    }

    cout << ans;

    return 0;
}

Subtask #1
82.0 / 100.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 1144 KB Output is correct
2 Correct 3 ms 1144 KB Output is correct
3 Correct 3 ms 1168 KB Output is correct
4 Correct 3 ms 1144 KB Output is correct
5 Correct 2 ms 1144 KB Output is correct
6 Correct 2 ms 1016 KB Output is correct
7 Correct 3 ms 1144 KB Output is correct
8 Correct 2 ms 1144 KB Output is correct
9 Correct 3 ms 1144 KB Output is correct
10 Correct 2 ms 1016 KB Output is correct
11 Correct 3 ms 1144 KB Output is correct
12 Correct 3 ms 1016 KB Output is correct
13 Correct 3 ms 1144 KB Output is correct
14 Correct 3 ms 1016 KB Output is correct
15 Correct 3 ms 1016 KB Output is correct
16 Correct 3 ms 1144 KB Output is correct
17 Correct 3 ms 1144 KB Output is correct
18 Correct 3 ms 1144 KB Output is correct
19 Correct 5 ms 1272 KB Output is correct
20 Correct 4 ms 1144 KB Output is correct
21 Correct 3 ms 1144 KB Output is correct
22 Correct 3 ms 1144 KB Output is correct
23 Correct 3 ms 1176 KB Output is correct
24 Correct 3 ms 1148 KB Output is correct
25 Correct 74 ms 1784 KB Output is correct
26 Correct 20 ms 1276 KB Output is correct
27 Correct 4 ms 1144 KB Output is correct
28 Correct 4 ms 1144 KB Output is correct
29 Correct 19 ms 1528 KB Output is correct
30 Correct 16 ms 1528 KB Output is correct
31 Correct 568 ms 2932 KB Output is correct
32 Correct 27 ms 1400 KB Output is correct
33 Correct 11 ms 1144 KB Output is correct
34 Correct 18 ms 1272 KB Output is correct
35 Correct 238 ms 4556 KB Output is correct
36 Correct 158 ms 4564 KB Output is correct
37 Execution timed out 1563 ms 3176 KB Time limit exceeded
38 Correct 339 ms 4932 KB Output is correct
39 Correct 677 ms 2224 KB Output is correct
40 Correct 665 ms 2288 KB Output is correct
41 Execution timed out 1575 ms 2416 KB Time limit exceeded
42 Correct 833 ms 3052 KB Output is correct
43 Correct 1197 ms 4716 KB Output is correct
44 Execution timed out 1568 ms 5236 KB Time limit exceeded
45 Execution timed out 1556 ms 4204 KB Time limit exceeded
46 Execution timed out 1566 ms 6244 KB Time limit exceeded
47 Execution timed out 1551 ms 8164 KB Time limit exceeded
48 Execution timed out 1549 ms 5992 KB Time limit exceeded
49 Execution timed out 1565 ms 8164 KB Time limit exceeded
50 Execution timed out 1564 ms 3308 KB Time limit exceeded