oj.uz

Submission #171844

# Submission time Handle Problem Language Result Execution time Memory
171844 2019-12-30T13:24:38 Z VEGAnn Marriage questions (IZhO14_marriage) C++14
82 / 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);
}

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 2 ms 1144 KB Output is correct
4 Correct 2 ms 1144 KB Output is correct
5 Correct 3 ms 1144 KB Output is correct
6 Correct 3 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 1132 KB Output is correct
10 Correct 3 ms 1244 KB Output is correct
11 Correct 2 ms 1016 KB Output is correct
12 Correct 3 ms 1144 KB Output is correct
13 Correct 2 ms 1144 KB Output is correct
14 Correct 3 ms 1144 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 2 ms 1144 KB Output is correct
19 Correct 5 ms 1144 KB Output is correct
20 Correct 4 ms 1144 KB Output is correct
21 Correct 3 ms 1148 KB Output is correct
22 Correct 3 ms 1136 KB Output is correct
23 Correct 3 ms 1144 KB Output is correct
24 Correct 3 ms 1136 KB Output is correct
25 Correct 72 ms 1656 KB Output is correct
26 Correct 19 ms 1272 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 1536 KB Output is correct
30 Correct 16 ms 1524 KB Output is correct
31 Correct 561 ms 2804 KB Output is correct
32 Correct 27 ms 1400 KB Output is correct
33 Correct 11 ms 1276 KB Output is correct
34 Correct 18 ms 1284 KB Output is correct
35 Correct 238 ms 4048 KB Output is correct
36 Correct 161 ms 4180 KB Output is correct
37 Execution timed out 1551 ms 2964 KB Time limit exceeded
38 Correct 330 ms 4040 KB Output is correct
39 Correct 678 ms 2072 KB Output is correct
40 Correct 614 ms 2156 KB Output is correct
41 Execution timed out 1566 ms 2284 KB Time limit exceeded
42 Correct 826 ms 2796 KB Output is correct
43 Correct 1190 ms 4204 KB Output is correct
44 Execution timed out 1561 ms 4432 KB Time limit exceeded
45 Execution timed out 1557 ms 3820 KB Time limit exceeded
46 Execution timed out 1568 ms 5220 KB Time limit exceeded
47 Execution timed out 1553 ms 7144 KB Time limit exceeded
48 Execution timed out 1572 ms 5228 KB Time limit exceeded
49 Execution timed out 1535 ms 7268 KB Time limit exceeded
50 Execution timed out 1576 ms 3308 KB Time limit exceeded