oj.uz

Submission #171856

# Submission time Handle Problem Language Result Execution time Memory
171856 2019-12-30T13:43:25 Z VEGAnn Marriage questions (IZhO14_marriage) C++14
80 / 100
 1500 ms 7924 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;
            if (!kok(l, r)) return -1;
            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 1016 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 1144 KB Output is correct
9 Runtime error 3 ms 1144 KB Execution failed because the return code was nonzero
10 Correct 3 ms 1016 KB Output is correct
11 Correct 3 ms 1148 KB Output is correct
12 Runtime error 3 ms 1144 KB Execution failed because the return code was nonzero
13 Correct 3 ms 1148 KB Output is correct
14 Correct 3 ms 1144 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 7 ms 1144 KB Output is correct
20 Correct 5 ms 1144 KB Output is correct
21 Runtime error 3 ms 1144 KB Execution failed because the return code was nonzero
22 Correct 4 ms 1144 KB Output is correct
23 Correct 4 ms 1144 KB Output is correct
24 Correct 3 ms 1144 KB Output is correct
25 Correct 81 ms 1656 KB Output is correct
26 Correct 35 ms 1400 KB Output is correct
27 Runtime error 4 ms 1144 KB Execution failed because the return code was nonzero
28 Correct 3 ms 1144 KB Output is correct
29 Correct 15 ms 1624 KB Output is correct
30 Correct 12 ms 1528 KB Output is correct
31 Correct 607 ms 2932 KB Output is correct
32 Correct 25 ms 1528 KB Output is correct
33 Runtime error 4 ms 1144 KB Execution failed because the return code was nonzero
34 Correct 7 ms 1272 KB Output is correct
35 Correct 279 ms 4560 KB Output is correct
36 Correct 187 ms 4560 KB Output is correct
37 Execution timed out 1551 ms 3180 KB Time limit exceeded
38 Correct 125 ms 4808 KB Output is correct
39 Correct 276 ms 2264 KB Output is correct
40 Runtime error 40 ms 2160 KB Execution failed because the return code was nonzero
41 Correct 1097 ms 2412 KB Output is correct
42 Correct 49 ms 3056 KB Output is correct
43 Correct 75 ms 4716 KB Output is correct
44 Correct 116 ms 4852 KB Output is correct
45 Execution timed out 1539 ms 3948 KB Time limit exceeded
46 Execution timed out 1561 ms 5860 KB Time limit exceeded
47 Correct 171 ms 7924 KB Output is correct
48 Correct 155 ms 5736 KB Output is correct
49 Execution timed out 1557 ms 7908 KB Time limit exceeded
50 Correct 1211 ms 3308 KB Output is correct