oj.uz

Submission #171857

# Submission time Handle Problem Language Result Execution time Memory
171857 2019-12-30T13:44:27 Z VEGAnn Marriage questions (IZhO14_marriage) C++14
80 / 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;
            }
            if (lf >= n) break;

            r = lf;
            while (!kok(l, r)) r++;

            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
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 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 3 ms 1016 KB Output is correct
7 Correct 3 ms 1144 KB Output is correct
8 Correct 3 ms 1020 KB Output is correct
9 Execution timed out 1525 ms 1144 KB Time limit exceeded
10 Correct 0 ms 1016 KB Output is correct
11 Correct 3 ms 1016 KB Output is correct
12 Execution timed out 1545 ms 1016 KB Time limit exceeded
13 Correct 3 ms 1144 KB Output is correct
14 Correct 3 ms 1016 KB Output is correct
15 Correct 3 ms 1144 KB Output is correct
16 Correct 2 ms 1020 KB Output is correct
17 Correct 3 ms 1016 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 Execution timed out 1554 ms 1144 KB Time limit exceeded
22 Correct 3 ms 1144 KB Output is correct
23 Correct 3 ms 1148 KB Output is correct
24 Correct 3 ms 1144 KB Output is correct
25 Correct 82 ms 1528 KB Output is correct
26 Correct 23 ms 1144 KB Output is correct
27 Execution timed out 1560 ms 1148 KB Time limit exceeded
28 Correct 3 ms 1144 KB Output is correct
29 Correct 15 ms 1500 KB Output is correct
30 Correct 13 ms 1528 KB Output is correct
31 Correct 617 ms 2548 KB Output is correct
32 Correct 24 ms 1400 KB Output is correct
33 Execution timed out 1519 ms 1144 KB Time limit exceeded
34 Correct 8 ms 1272 KB Output is correct
35 Correct 283 ms 3792 KB Output is correct
36 Correct 185 ms 3924 KB Output is correct
37 Execution timed out 1564 ms 2668 KB Time limit exceeded
38 Correct 127 ms 4044 KB Output is correct
39 Correct 275 ms 2116 KB Output is correct
40 Execution timed out 1565 ms 2036 KB Time limit exceeded
41 Correct 1113 ms 2312 KB Output is correct
42 Correct 49 ms 2800 KB Output is correct
43 Correct 77 ms 4200 KB Output is correct
44 Correct 115 ms 4176 KB Output is correct
45 Execution timed out 1571 ms 3692 KB Time limit exceeded
46 Execution timed out 1570 ms 5220 KB Time limit exceeded
47 Correct 171 ms 7140 KB Output is correct
48 Correct 154 ms 5100 KB Output is correct
49 Execution timed out 1567 ms 7268 KB Time limit exceeded
50 Correct 1204 ms 3304 KB Output is correct