답안 #66462 :: oj.uz

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
66462	2018-08-10T16:03:44 Z	aquablitz11	낙하산 고리들 (IOI12_rings)	C++14	55 / 100	4000 ms	96452 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
 
bool dead[N];
inline bool test(int u) {
    //fprintf(stderr, "test(%d)\n", u);
    if (dead[u]) return false;
    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());
 
    if (!ok) dead[u] = true;
    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 (cnt4 > 1) return 0;
    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;
    int cnt = 0;
    if (test(mxdeg.second)) ++cnt;
    if (mxdeg.first == 3) {
        for (auto v : G[mxdeg.second])
            if (test(v)) ++cnt;
    }
    return cnt;
}

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	27 ms	24060 KB	Output is correct
3	Correct	25 ms	24360 KB	Output is correct
4	Correct	23 ms	24360 KB	Output is correct
5	Correct	24 ms	24360 KB	Output is correct
6	Correct	26 ms	24612 KB	Output is correct
7	Correct	23 ms	24612 KB	Output is correct
8	Correct	25 ms	24612 KB	Output is correct
9	Correct	24 ms	24612 KB	Output is correct
10	Correct	24 ms	24612 KB	Output is correct

Subtask #2
17.0 / 17.0

#	결과	실행 시간	메모리	Grader output
1	Correct	430 ms	46564 KB	Output is correct
2	Correct	895 ms	58556 KB	Output is correct
3	Correct	1125 ms	62860 KB	Output is correct
4	Correct	1238 ms	67132 KB	Output is correct
5	Correct	1188 ms	68392 KB	Output is correct
6	Correct	1310 ms	96452 KB	Output is correct
7	Correct	1109 ms	96452 KB	Output is correct
8	Correct	1164 ms	96452 KB	Output is correct
9	Correct	1222 ms	96452 KB	Output is correct
10	Correct	827 ms	96452 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	27 ms	24060 KB	Output is correct
3	Correct	25 ms	24360 KB	Output is correct
4	Correct	23 ms	24360 KB	Output is correct
5	Correct	24 ms	24360 KB	Output is correct
6	Correct	26 ms	24612 KB	Output is correct
7	Correct	23 ms	24612 KB	Output is correct
8	Correct	25 ms	24612 KB	Output is correct
9	Correct	24 ms	24612 KB	Output is correct
10	Correct	24 ms	24612 KB	Output is correct
11	Correct	23 ms	96452 KB	Output is correct
12	Correct	26 ms	96452 KB	Output is correct
13	Correct	27 ms	96452 KB	Output is correct
14	Correct	27 ms	96452 KB	Output is correct
15	Correct	28 ms	96452 KB	Output is correct
16	Correct	28 ms	96452 KB	Output is correct
17	Correct	28 ms	96452 KB	Output is correct
18	Correct	28 ms	96452 KB	Output is correct
19	Correct	26 ms	96452 KB	Output is correct
20	Correct	27 ms	96452 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	27 ms	24060 KB	Output is correct
3	Correct	25 ms	24360 KB	Output is correct
4	Correct	23 ms	24360 KB	Output is correct
5	Correct	24 ms	24360 KB	Output is correct
6	Correct	26 ms	24612 KB	Output is correct
7	Correct	23 ms	24612 KB	Output is correct
8	Correct	25 ms	24612 KB	Output is correct
9	Correct	24 ms	24612 KB	Output is correct
10	Correct	24 ms	24612 KB	Output is correct
11	Correct	23 ms	96452 KB	Output is correct
12	Correct	26 ms	96452 KB	Output is correct
13	Correct	27 ms	96452 KB	Output is correct
14	Correct	27 ms	96452 KB	Output is correct
15	Correct	28 ms	96452 KB	Output is correct
16	Correct	28 ms	96452 KB	Output is correct
17	Correct	28 ms	96452 KB	Output is correct
18	Correct	28 ms	96452 KB	Output is correct
19	Correct	26 ms	96452 KB	Output is correct
20	Correct	27 ms	96452 KB	Output is correct
21	Correct	44 ms	96452 KB	Output is correct
22	Correct	57 ms	96452 KB	Output is correct
23	Correct	70 ms	96452 KB	Output is correct
24	Execution timed out	4038 ms	96452 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	27 ms	24060 KB	Output is correct
3	Correct	25 ms	24360 KB	Output is correct
4	Correct	23 ms	24360 KB	Output is correct
5	Correct	24 ms	24360 KB	Output is correct
6	Correct	26 ms	24612 KB	Output is correct
7	Correct	23 ms	24612 KB	Output is correct
8	Correct	25 ms	24612 KB	Output is correct
9	Correct	24 ms	24612 KB	Output is correct
10	Correct	24 ms	24612 KB	Output is correct
11	Correct	430 ms	46564 KB	Output is correct
12	Correct	895 ms	58556 KB	Output is correct
13	Correct	1125 ms	62860 KB	Output is correct
14	Correct	1238 ms	67132 KB	Output is correct
15	Correct	1188 ms	68392 KB	Output is correct
16	Correct	1310 ms	96452 KB	Output is correct
17	Correct	1109 ms	96452 KB	Output is correct
18	Correct	1164 ms	96452 KB	Output is correct
19	Correct	1222 ms	96452 KB	Output is correct
20	Correct	827 ms	96452 KB	Output is correct
21	Correct	23 ms	96452 KB	Output is correct
22	Correct	26 ms	96452 KB	Output is correct
23	Correct	27 ms	96452 KB	Output is correct
24	Correct	27 ms	96452 KB	Output is correct
25	Correct	28 ms	96452 KB	Output is correct
26	Correct	28 ms	96452 KB	Output is correct
27	Correct	28 ms	96452 KB	Output is correct
28	Correct	28 ms	96452 KB	Output is correct
29	Correct	26 ms	96452 KB	Output is correct
30	Correct	27 ms	96452 KB	Output is correct
31	Correct	44 ms	96452 KB	Output is correct
32	Correct	57 ms	96452 KB	Output is correct
33	Correct	70 ms	96452 KB	Output is correct
34	Execution timed out	4038 ms	96452 KB	Time limit exceeded
35	Halted	0 ms	0 KB	-

답안 #66462

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