oj.uz

Submission #171827

# Submission time Handle Problem Language Result Execution time Memory
171827 2019-12-30T13:00:47 Z VEGAnn Marriage questions (IZhO14_marriage) C++14
80 / 100
 1500 ms 8164 KB 
#include <bits/stdc++.h>
#define sz(x) ((int)x.size())
#define PB push_back
#define MP make_pair
#define ft first
#define sd second
#define pii pair<int, int>
#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;

struct edge{
    int y;
    bool psh;

    edge(int _y, bool _p): y(_y), psh(_p) {}
};

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
80.0 / 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 2 ms 1020 KB Output is correct
4 Correct 3 ms 1144 KB Output is correct
5 Correct 3 ms 1020 KB Output is correct
6 Correct 9 ms 1144 KB Output is correct
7 Correct 3 ms 1144 KB Output is correct
8 Correct 3 ms 1016 KB Output is correct
9 Correct 3 ms 1148 KB Output is correct
10 Correct 3 ms 1144 KB Output is correct
11 Correct 3 ms 1144 KB Output is correct
12 Correct 3 ms 1144 KB Output is correct
13 Correct 3 ms 1144 KB Output is correct
14 Correct 3 ms 1148 KB Output is correct
15 Correct 3 ms 1144 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 6 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 1144 KB Output is correct
24 Correct 3 ms 1144 KB Output is correct
25 Correct 80 ms 1656 KB Output is correct
26 Correct 22 ms 1272 KB Output is correct
27 Correct 4 ms 1144 KB Output is correct
28 Correct 4 ms 1192 KB Output is correct
29 Correct 22 ms 1624 KB Output is correct
30 Correct 18 ms 1528 KB Output is correct
31 Correct 601 ms 2932 KB Output is correct
32 Correct 28 ms 1400 KB Output is correct
33 Correct 12 ms 1400 KB Output is correct
34 Correct 18 ms 1272 KB Output is correct
35 Correct 268 ms 4552 KB Output is correct
36 Correct 180 ms 4556 KB Output is correct
37 Execution timed out 1570 ms 3184 KB Time limit exceeded
38 Correct 367 ms 4932 KB Output is correct
39 Correct 718 ms 2188 KB Output is correct
40 Correct 731 ms 2164 KB Output is correct
41 Execution timed out 1581 ms 2416 KB Time limit exceeded
42 Correct 1110 ms 3176 KB Output is correct
43 Execution timed out 1507 ms 4584 KB Time limit exceeded
44 Execution timed out 1559 ms 5204 KB Time limit exceeded
45 Execution timed out 1576 ms 4204 KB Time limit exceeded
46 Execution timed out 1583 ms 5988 KB Time limit exceeded
47 Execution timed out 1569 ms 8164 KB Time limit exceeded
48 Execution timed out 1563 ms 6004 KB Time limit exceeded
49 Execution timed out 1569 ms 8164 KB Time limit exceeded
50 Execution timed out 1570 ms 3280 KB Time limit exceeded