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Submission #96044

# Submission time Handle Problem Language Result Execution time Memory
96044 2019-02-05T11:37:04 Z Kastanda Marriage questions (IZhO14_marriage) C++11
100 / 100
 1314 ms 5812 KB 
#include<bits/stdc++.h>
#define pb push_back
using namespace std;
const int MAXN = 34004, MAXM = 268900;
int s, t, P[MAXN], qu[MAXN];
int ts, to[MAXM], flow[MAXM];
int head[MAXN], nxt[MAXM];
int ptr, mm;
inline void AddEdge(int v, int u, int w)
{
    nxt[ts] = head[v]; head[v] = ts;
    to[ts] = u; flow[ts] = w; ts ++;
    nxt[ts] = head[u]; head[u] = ts;
    to[ts] = v; flow[ts] = 0; ts ++;
}
inline bool BFS()
{
    int l = 0, r = 0;
    memset(P, -1, sizeof(P));
    qu[r ++] = s;
    while (r - l)
    {
        int v = qu[l ++];
        while (~head[v] && mm < to[head[v]] && to[head[v]] <= ptr)
            head[v] = nxt[head[v]];
        for (int id = head[v], p = id; ~id; p = id, id = nxt[id])
        {
            if (mm < to[id] && to[id] <= ptr)
                nxt[p] = nxt[id], id = p;
            else if (flow[id] && P[to[id]] == -1)
            {
                P[to[id]] = id;
                if (to[id] == t)
                    return (1);
                qu[r ++] = to[id];
            }
        }
    }
    return (0);
}
inline int MaxFlow()
{
    int Flow = 0;
    while (BFS())
    {
        int v = t, _flow = INT_MAX;
        while (v != s)
            _flow = min(_flow, flow[P[v]]), v = to[P[v]^1];
        Flow += _flow; v = t;
        while (v != s)
        {
            flow[P[v]] -= _flow;
            flow[P[v]^1] += _flow;
            v = to[P[v]^1];
        }
    }
    return Flow;
}
int n, m, k, source, sink;
int tff[2003];
vector < int > vec[MAXN];
inline void Add(int v)
{
    for (int &u : vec[v])
        AddEdge(u, v + m, 1);
    AddEdge(v + m, sink, 1);
}
inline int Del(int v)
{
    v += m;
    if (flow[head[v]])
    {
        flow[head[v]] = 0;
        //for (int e = head[v]; ~e; e = nxt[e])
            //flow[e^1] = 0;
        return (0);
    }
    flow[head[v]^1] = 0;
    int e = head[v];
    for (; !flow[e]; e = nxt[e]);
    int u = to[e];
    flow[e] = 0;
    flow[tff[u]] = 0;
    flow[tff[u]^1] = 1;
    return (1);
}
int main()
{
    memset(head, -1, sizeof(head));
    memset(nxt, -1, sizeof(nxt));

    scanf("%d%d%d", &n, &m, &k);
    for (int i = 1; i <= k; i++)
    {
        int v, u;
        scanf("%d%d", &v, &u);
        vec[v].pb(u);
        //AddEdge(u, v + m, 1);
    }
    source = 0; sink = n + m + 1;
    s = source; t = sink;
    for (int i = 1; i <= m; i++)
        AddEdge(source, i, 1), tff[i] = ts - 1;
    //for (int i = 1; i <= n; i++)
        //AddEdge(m + i, sink, 0);
    int r = 0, Flow = 0;
    int tot = 0;
    ptr = mm = m;
    for (int l = 1; l <= n; l ++)
    {
        while (r < l)
            r ++, Add(r);
        Flow += MaxFlow();
        while (r < n && Flow < m)
            r ++, Add(r), Flow += MaxFlow();
        if (Flow < m)
            break;
        tot += n - r + 1;
        Flow -= Del(l);
        ptr ++;
    }
    return !printf("%d\n", tot);
}

Compilation message

marriage.cpp: In function 'int main()':
marriage.cpp:92:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d%d", &n, &m, &k);
     ~~~~~^~~~~~~~~~~~~~~~~~~~~~
marriage.cpp:96:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d%d", &v, &u);
         ~~~~~^~~~~~~~~~~~~~~~

Subtask #1
100.0 / 100.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 2424 KB Output is correct
2 Correct 4 ms 2424 KB Output is correct
3 Correct 4 ms 2424 KB Output is correct
4 Correct 4 ms 2424 KB Output is correct
5 Correct 3 ms 2424 KB Output is correct
6 Correct 4 ms 2424 KB Output is correct
7 Correct 4 ms 2424 KB Output is correct
8 Correct 4 ms 2424 KB Output is correct
9 Correct 4 ms 2424 KB Output is correct
10 Correct 3 ms 2424 KB Output is correct
11 Correct 4 ms 2424 KB Output is correct
12 Correct 4 ms 2428 KB Output is correct
13 Correct 3 ms 2424 KB Output is correct
14 Correct 4 ms 2424 KB Output is correct
15 Correct 4 ms 2424 KB Output is correct
16 Correct 4 ms 2424 KB Output is correct
17 Correct 4 ms 2424 KB Output is correct
18 Correct 4 ms 2424 KB Output is correct
19 Correct 7 ms 2552 KB Output is correct
20 Correct 5 ms 2424 KB Output is correct
21 Correct 4 ms 2424 KB Output is correct
22 Correct 4 ms 2424 KB Output is correct
23 Correct 5 ms 2552 KB Output is correct
24 Correct 4 ms 2424 KB Output is correct
25 Correct 29 ms 2696 KB Output is correct
26 Correct 15 ms 2552 KB Output is correct
27 Correct 8 ms 2424 KB Output is correct
28 Correct 9 ms 2396 KB Output is correct
29 Correct 10 ms 2680 KB Output is correct
30 Correct 10 ms 2680 KB Output is correct
31 Correct 540 ms 3660 KB Output is correct
32 Correct 32 ms 2680 KB Output is correct
33 Correct 20 ms 2424 KB Output is correct
34 Correct 23 ms 2552 KB Output is correct
35 Correct 415 ms 4608 KB Output is correct
36 Correct 290 ms 4304 KB Output is correct
37 Correct 1314 ms 3860 KB Output is correct
38 Correct 56 ms 4856 KB Output is correct
39 Correct 377 ms 2804 KB Output is correct
40 Correct 334 ms 3044 KB Output is correct
41 Correct 373 ms 3224 KB Output is correct
42 Correct 168 ms 3576 KB Output is correct
43 Correct 176 ms 3960 KB Output is correct
44 Correct 262 ms 4672 KB Output is correct
45 Correct 782 ms 4120 KB Output is correct
46 Correct 1076 ms 5600 KB Output is correct
47 Correct 500 ms 5540 KB Output is correct
48 Correct 462 ms 5216 KB Output is correct
49 Correct 1128 ms 5812 KB Output is correct
50 Correct 996 ms 3268 KB Output is correct