oj.uz

Submission #171859

# Submission time Handle Problem Language Result Execution time Memory
171859 2019-12-30T13:46:02 Z VEGAnn Marriage questions (IZhO14_marriage) C++14
92 / 100
 1500 ms 7268 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);
}

bool kok(int l, int r){

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

    for (int it = 0; it < sz(edges); it += 2){
        edges[it].psh = 0;
        edges[it ^ 1].psh = 1;
    }

    int flow = 0;

    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;

        if (l == 0){
            int lf = m - 1, rt = n - 1;
            while (lf < rt){
                int md = (lf + rt) >> 1;
                if (kok(l, md))
                    rt = md;
                else lf = md + 1;
            }
            r = lf;
            while (r < n && !kok(l, r)) r++;

            if (r >= n) break;
            kok(l, r);
            ans += n - r;
        } else {

            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
92.0 / 100.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 1016 KB Output is correct
2 Correct 3 ms 1144 KB Output is correct
3 Correct 3 ms 1144 KB Output is correct
4 Correct 3 ms 1016 KB Output is correct
5 Correct 3 ms 1144 KB Output is correct
6 Correct 4 ms 1016 KB Output is correct
7 Correct 3 ms 1016 KB Output is correct
8 Correct 3 ms 1144 KB Output is correct
9 Correct 3 ms 1144 KB Output is correct
10 Correct 2 ms 1020 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 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 6 ms 1144 KB Output is correct
20 Correct 4 ms 1144 KB Output is correct
21 Correct 3 ms 1144 KB Output is correct
22 Correct 4 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 74 ms 1528 KB Output is correct
26 Correct 22 ms 1404 KB Output is correct
27 Correct 3 ms 1016 KB Output is correct
28 Correct 3 ms 1144 KB Output is correct
29 Correct 14 ms 1528 KB Output is correct
30 Correct 12 ms 1528 KB Output is correct
31 Correct 578 ms 2676 KB Output is correct
32 Correct 24 ms 1400 KB Output is correct
33 Correct 4 ms 1272 KB Output is correct
34 Correct 8 ms 1272 KB Output is correct
35 Correct 249 ms 3916 KB Output is correct
36 Correct 169 ms 4048 KB Output is correct
37 Execution timed out 1554 ms 2672 KB Time limit exceeded
38 Correct 118 ms 4164 KB Output is correct
39 Correct 254 ms 2036 KB Output is correct
40 Correct 36 ms 2032 KB Output is correct
41 Correct 972 ms 2416 KB Output is correct
42 Correct 38 ms 2800 KB Output is correct
43 Correct 62 ms 4208 KB Output is correct
44 Correct 100 ms 4276 KB Output is correct
45 Execution timed out 1558 ms 3692 KB Time limit exceeded
46 Execution timed out 1552 ms 5220 KB Time limit exceeded
47 Correct 137 ms 7140 KB Output is correct
48 Correct 135 ms 5100 KB Output is correct
49 Execution timed out 1559 ms 7268 KB Time limit exceeded
50 Correct 980 ms 3184 KB Output is correct