oj.uz

Submission #171838

# Submission time Handle Problem Language Result Execution time Memory
171838 2019-12-30T13:19:51 Z VEGAnn Marriage questions (IZhO14_marriage) C++14
82 / 100
 1500 ms 8188 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, 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;

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 1144 KB Output is correct
4 Correct 3 ms 1296 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 2 ms 1016 KB Output is correct
9 Correct 3 ms 1016 KB Output is correct
10 Correct 3 ms 1016 KB Output is correct
11 Correct 3 ms 1016 KB Output is correct
12 Correct 3 ms 1012 KB Output is correct
13 Correct 3 ms 1144 KB Output is correct
14 Correct 2 ms 1016 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 2 ms 1144 KB Output is correct
19 Correct 6 ms 1272 KB Output is correct
20 Correct 3 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 1172 KB Output is correct
25 Correct 73 ms 1656 KB Output is correct
26 Correct 19 ms 1316 KB Output is correct
27 Correct 4 ms 1172 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 562 ms 2932 KB Output is correct
32 Correct 27 ms 1404 KB Output is correct
33 Correct 11 ms 1148 KB Output is correct
34 Correct 18 ms 1276 KB Output is correct
35 Correct 240 ms 4564 KB Output is correct
36 Correct 156 ms 4608 KB Output is correct
37 Execution timed out 1573 ms 3052 KB Time limit exceeded
38 Correct 338 ms 4932 KB Output is correct
39 Correct 678 ms 2100 KB Output is correct
40 Correct 626 ms 2160 KB Output is correct
41 Execution timed out 1509 ms 2432 KB Time limit exceeded
42 Correct 828 ms 3056 KB Output is correct
43 Correct 1196 ms 4588 KB Output is correct
44 Execution timed out 1567 ms 5116 KB Time limit exceeded
45 Execution timed out 1554 ms 3980 KB Time limit exceeded
46 Execution timed out 1576 ms 6104 KB Time limit exceeded
47 Execution timed out 1555 ms 8188 KB Time limit exceeded
48 Execution timed out 1581 ms 5868 KB Time limit exceeded
49 Execution timed out 1572 ms 8164 KB Time limit exceeded
50 Execution timed out 1580 ms 3308 KB Time limit exceeded