답안 #66460 :: oj.uz

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
66460	2018-08-10T15:59:24 Z	aquablitz11	낙하산 고리들 (IOI12_rings)	C++14	55 / 100	4000 ms	96412 KB

rings

#include <bits/stdc++.h>
using namespace std;
using pii = pair<int, int>;
const int N = 1e6+10;
 
// graph data
 
int n;
vector<pii> E, ES;
vector<int> G[N];
 
int dfs(int u, int p, int s, int t)
{
    if (u == t)
        return 1;
    for (auto v : G[u]) if (v != p && (u != s || v != t)) {
        int r = dfs(v, u, s, t);
        if (r) return r+1;
    }
    return 0;
}
 
// dsu with copying for experimentation
 
bool ffc = true;
int par[N], mfcnt, firstcycle;
int root(int u) {
    if (par[u] == u) return u;
    return par[u] = root(par[u]);
}
inline bool merge(int u, int v) {
    //fprintf(stderr, "merge(%d, %d)\n", u, v);
    int u0 = u, v0 = v;
    u = root(u), v = root(v);
    if (u == v) {
        if (++mfcnt == 1 && ffc)
            firstcycle = dfs(u0, -1, u0, v0);
        return false;
    }
    par[u] = v;
    return true;
}
int _np[N], _nv[N], tick;
inline int &np(int u) {
    if (_nv[u] != tick) {
        _np[u] = par[u];
        _nv[u] = tick;
    }
    return _np[u];
}
int nroot(int u) {
    if (np(u) == u) return u;
    return np(u) = nroot(np(u));
}
inline bool nmerge(int u, int v) {
    //fprintf(stderr, "nmerge(%d, %d)\n", u, v);
    u = nroot(u), v = nroot(v);
    if (u == v) return false;
    np(u) = v;
    return true;
}
 
// state control (degree freq. histogram)
 
int cntok, cnt3, cnt4;
pii mxdeg(0, -1);
 
inline void testmod(int a, int b) {
    if (a <= 2) --cntok;
    if (a == 3) --cnt3;
    if (a >= 4) --cnt4;
    if (b <= 2) ++cntok;
    if (b == 3) ++cnt3;
    if (b >= 4) ++cnt4;
}
 
// rebuild dsu with exceptions
 
inline bool must_skip(int u) {
    if (mxdeg.first < 3)
        return false;
    if (u == mxdeg.second)
        return true;
    if (mxdeg.first == 3) {
        for (auto v : G[mxdeg.second]) if (v == u)
            return true;
    }
    return false;
}
 
inline void build_dsu() {
    //fprintf(stderr, "rebuild dsu!\n");
    ES.clear();
    mfcnt = 0;
    for (int i = 0; i < n; ++i)
        par[i] = i;
    for (auto e : E) {
        int u = e.first, v = e.second;
        if (must_skip(u) || must_skip(v)) {
            ES.emplace_back(u, v);
            //fprintf(stderr, "skip edge %d %d\n", u, v);
            continue;
        }
        merge(e.first, e.second);
    }
}
 
inline bool modify(int u) {
    testmod(G[u].size()-1, G[u].size());
    if (G[u].size() > mxdeg.first) {
        mxdeg = pii(G[u].size(), u);
        if (mxdeg.first == 3 || mxdeg.first == 4) {
            ffc = false;
            return true;
        }
    }
    return false;
}
 
// testing functions
 
inline bool test(int u) {
    //fprintf(stderr, "test(%d)\n", u);
    testmod(G[u].size(), 0);
    for (auto v : G[u])
        testmod(G[v].size(), G[v].size()-1);
 
    bool ok = cnt3 == 0 && cnt4 == 0;
    ++tick;
    if (ok) for (auto e : ES) {
        if (e.first == u || e.second == u) continue;
        if (!nmerge(e.first, e.second)) ok = false;
        if (!ok) break;
    }
 
    testmod(0, G[u].size());
    for (auto v : G[u])
        testmod(G[v].size()-1, G[v].size());
 
    return ok;
}
 
// problem functions:
 
void Init(int n) {
    //fprintf(stderr, "Init(%d)\n", n);
    ::n = n;
    build_dsu();
}
 
void Link(int u, int v) {
    //fprintf(stderr, "Link(%d, %d)\n", u, v);
    G[u].push_back(v);
    G[v].push_back(u);
    bool m = modify(u) | modify(v);
    E.emplace_back(u, v);
    if (m)
        build_dsu();
    else if (!must_skip(u) && !must_skip(v))
        merge(u, v);
    else
        ES.emplace_back(u, v);
}
 
int CountCritical() {
    //fprintf(stderr, "CountCritical()\n");
    if (mxdeg.first <= 2) {
        if (mfcnt > 1) return 0;
        else if (mfcnt == 1) return firstcycle;
        else if (mfcnt == 0) return n;
    }
    if (mfcnt > 0) return 0;
    if (mxdeg.first == 3) {
        int cnt = 0;
        if (test(mxdeg.second)) ++cnt;
        for (auto v : G[mxdeg.second])
            if (test(v)) ++cnt;
        return cnt;
    }
    return test(mxdeg.second) ? 1 : 0;
}

Compilation message

rings.cpp: In function 'bool modify(int)':
rings.cpp:110:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     if (G[u].size() > mxdeg.first) {
         ~~~~~~~~~~~~^~~~~~~~~~~~~

Subtask #1
20.0 / 20.0

#	결과	실행 시간	메모리	Grader output
1	Correct	22 ms	23800 KB	Output is correct
2	Correct	24 ms	24180 KB	Output is correct
3	Correct	25 ms	24296 KB	Output is correct
4	Correct	22 ms	24296 KB	Output is correct
5	Correct	25 ms	24296 KB	Output is correct
6	Correct	24 ms	24504 KB	Output is correct
7	Correct	23 ms	24504 KB	Output is correct
8	Correct	23 ms	24504 KB	Output is correct
9	Correct	26 ms	24508 KB	Output is correct
10	Correct	25 ms	24508 KB	Output is correct

Subtask #2
17.0 / 17.0

#	결과	실행 시간	메모리	Grader output
1	Correct	457 ms	46492 KB	Output is correct
2	Correct	944 ms	58532 KB	Output is correct
3	Correct	1179 ms	62760 KB	Output is correct
4	Correct	1206 ms	67184 KB	Output is correct
5	Correct	1223 ms	68516 KB	Output is correct
6	Correct	1294 ms	96412 KB	Output is correct
7	Correct	1171 ms	96412 KB	Output is correct
8	Correct	1200 ms	96412 KB	Output is correct
9	Correct	1338 ms	96412 KB	Output is correct
10	Correct	898 ms	96412 KB	Output is correct

Subtask #3
18.0 / 18.0

#	결과	실행 시간	메모리	Grader output
1	Correct	22 ms	23800 KB	Output is correct
2	Correct	24 ms	24180 KB	Output is correct
3	Correct	25 ms	24296 KB	Output is correct
4	Correct	22 ms	24296 KB	Output is correct
5	Correct	25 ms	24296 KB	Output is correct
6	Correct	24 ms	24504 KB	Output is correct
7	Correct	23 ms	24504 KB	Output is correct
8	Correct	23 ms	24504 KB	Output is correct
9	Correct	26 ms	24508 KB	Output is correct
10	Correct	25 ms	24508 KB	Output is correct
11	Correct	28 ms	96412 KB	Output is correct
12	Correct	35 ms	96412 KB	Output is correct
13	Correct	30 ms	96412 KB	Output is correct
14	Correct	30 ms	96412 KB	Output is correct
15	Correct	30 ms	96412 KB	Output is correct
16	Correct	39 ms	96412 KB	Output is correct
17	Correct	31 ms	96412 KB	Output is correct
18	Correct	30 ms	96412 KB	Output is correct
19	Correct	33 ms	96412 KB	Output is correct
20	Correct	29 ms	96412 KB	Output is correct

Subtask #4
0 / 14.0

#	결과	실행 시간	메모리	Grader output
1	Correct	22 ms	23800 KB	Output is correct
2	Correct	24 ms	24180 KB	Output is correct
3	Correct	25 ms	24296 KB	Output is correct
4	Correct	22 ms	24296 KB	Output is correct
5	Correct	25 ms	24296 KB	Output is correct
6	Correct	24 ms	24504 KB	Output is correct
7	Correct	23 ms	24504 KB	Output is correct
8	Correct	23 ms	24504 KB	Output is correct
9	Correct	26 ms	24508 KB	Output is correct
10	Correct	25 ms	24508 KB	Output is correct
11	Correct	28 ms	96412 KB	Output is correct
12	Correct	35 ms	96412 KB	Output is correct
13	Correct	30 ms	96412 KB	Output is correct
14	Correct	30 ms	96412 KB	Output is correct
15	Correct	30 ms	96412 KB	Output is correct
16	Correct	39 ms	96412 KB	Output is correct
17	Correct	31 ms	96412 KB	Output is correct
18	Correct	30 ms	96412 KB	Output is correct
19	Correct	33 ms	96412 KB	Output is correct
20	Correct	29 ms	96412 KB	Output is correct
21	Correct	65 ms	96412 KB	Output is correct
22	Correct	73 ms	96412 KB	Output is correct
23	Correct	80 ms	96412 KB	Output is correct
24	Execution timed out	4033 ms	96412 KB	Time limit exceeded
25	Halted	0 ms	0 KB	-

Subtask #5
0 / 31.0

#	결과	실행 시간	메모리	Grader output
1	Correct	22 ms	23800 KB	Output is correct
2	Correct	24 ms	24180 KB	Output is correct
3	Correct	25 ms	24296 KB	Output is correct
4	Correct	22 ms	24296 KB	Output is correct
5	Correct	25 ms	24296 KB	Output is correct
6	Correct	24 ms	24504 KB	Output is correct
7	Correct	23 ms	24504 KB	Output is correct
8	Correct	23 ms	24504 KB	Output is correct
9	Correct	26 ms	24508 KB	Output is correct
10	Correct	25 ms	24508 KB	Output is correct
11	Correct	457 ms	46492 KB	Output is correct
12	Correct	944 ms	58532 KB	Output is correct
13	Correct	1179 ms	62760 KB	Output is correct
14	Correct	1206 ms	67184 KB	Output is correct
15	Correct	1223 ms	68516 KB	Output is correct
16	Correct	1294 ms	96412 KB	Output is correct
17	Correct	1171 ms	96412 KB	Output is correct
18	Correct	1200 ms	96412 KB	Output is correct
19	Correct	1338 ms	96412 KB	Output is correct
20	Correct	898 ms	96412 KB	Output is correct
21	Correct	28 ms	96412 KB	Output is correct
22	Correct	35 ms	96412 KB	Output is correct
23	Correct	30 ms	96412 KB	Output is correct
24	Correct	30 ms	96412 KB	Output is correct
25	Correct	30 ms	96412 KB	Output is correct
26	Correct	39 ms	96412 KB	Output is correct
27	Correct	31 ms	96412 KB	Output is correct
28	Correct	30 ms	96412 KB	Output is correct
29	Correct	33 ms	96412 KB	Output is correct
30	Correct	29 ms	96412 KB	Output is correct
31	Correct	65 ms	96412 KB	Output is correct
32	Correct	73 ms	96412 KB	Output is correct
33	Correct	80 ms	96412 KB	Output is correct
34	Execution timed out	4033 ms	96412 KB	Time limit exceeded
35	Halted	0 ms	0 KB	-

답안 #66460

Compilation message

Subtask #1 20.0 / 20.0

Subtask #2 17.0 / 17.0

Subtask #3 18.0 / 18.0

Subtask #4 0 / 14.0

Subtask #5 0 / 31.0

Subtask #1
20.0 / 20.0

Subtask #2
17.0 / 17.0

Subtask #3
18.0 / 18.0

Subtask #4
0 / 14.0

Subtask #5
0 / 31.0