답안 #66457 :: oj.uz

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
66457	2018-08-10T15:57:43 Z	aquablitz11	낙하산 고리들 (IOI12_rings)	C++14	55 / 100	4000 ms	96344 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]);
}
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;
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));
}
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);
 
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
 
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;
}
 
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);
    }
}
 
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 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	23804 KB	Output is correct
2	Correct	24 ms	24052 KB	Output is correct
3	Correct	25 ms	24276 KB	Output is correct
4	Correct	24 ms	24276 KB	Output is correct
5	Correct	23 ms	24276 KB	Output is correct
6	Correct	24 ms	24496 KB	Output is correct
7	Correct	22 ms	24496 KB	Output is correct
8	Correct	24 ms	24496 KB	Output is correct
9	Correct	27 ms	24496 KB	Output is correct
10	Correct	24 ms	24496 KB	Output is correct

Subtask #2
17.0 / 17.0

#	결과	실행 시간	메모리	Grader output
1	Correct	463 ms	46664 KB	Output is correct
2	Correct	955 ms	58536 KB	Output is correct
3	Correct	1223 ms	62648 KB	Output is correct
4	Correct	1195 ms	67280 KB	Output is correct
5	Correct	1221 ms	68520 KB	Output is correct
6	Correct	1300 ms	96344 KB	Output is correct
7	Correct	1106 ms	96344 KB	Output is correct
8	Correct	1157 ms	96344 KB	Output is correct
9	Correct	1319 ms	96344 KB	Output is correct
10	Correct	879 ms	96344 KB	Output is correct

Subtask #3
18.0 / 18.0

#	결과	실행 시간	메모리	Grader output
1	Correct	22 ms	23804 KB	Output is correct
2	Correct	24 ms	24052 KB	Output is correct
3	Correct	25 ms	24276 KB	Output is correct
4	Correct	24 ms	24276 KB	Output is correct
5	Correct	23 ms	24276 KB	Output is correct
6	Correct	24 ms	24496 KB	Output is correct
7	Correct	22 ms	24496 KB	Output is correct
8	Correct	24 ms	24496 KB	Output is correct
9	Correct	27 ms	24496 KB	Output is correct
10	Correct	24 ms	24496 KB	Output is correct
11	Correct	25 ms	96344 KB	Output is correct
12	Correct	30 ms	96344 KB	Output is correct
13	Correct	29 ms	96344 KB	Output is correct
14	Correct	35 ms	96344 KB	Output is correct
15	Correct	28 ms	96344 KB	Output is correct
16	Correct	29 ms	96344 KB	Output is correct
17	Correct	27 ms	96344 KB	Output is correct
18	Correct	38 ms	96344 KB	Output is correct
19	Correct	29 ms	96344 KB	Output is correct
20	Correct	34 ms	96344 KB	Output is correct

Subtask #4
0 / 14.0

#	결과	실행 시간	메모리	Grader output
1	Correct	22 ms	23804 KB	Output is correct
2	Correct	24 ms	24052 KB	Output is correct
3	Correct	25 ms	24276 KB	Output is correct
4	Correct	24 ms	24276 KB	Output is correct
5	Correct	23 ms	24276 KB	Output is correct
6	Correct	24 ms	24496 KB	Output is correct
7	Correct	22 ms	24496 KB	Output is correct
8	Correct	24 ms	24496 KB	Output is correct
9	Correct	27 ms	24496 KB	Output is correct
10	Correct	24 ms	24496 KB	Output is correct
11	Correct	25 ms	96344 KB	Output is correct
12	Correct	30 ms	96344 KB	Output is correct
13	Correct	29 ms	96344 KB	Output is correct
14	Correct	35 ms	96344 KB	Output is correct
15	Correct	28 ms	96344 KB	Output is correct
16	Correct	29 ms	96344 KB	Output is correct
17	Correct	27 ms	96344 KB	Output is correct
18	Correct	38 ms	96344 KB	Output is correct
19	Correct	29 ms	96344 KB	Output is correct
20	Correct	34 ms	96344 KB	Output is correct
21	Correct	44 ms	96344 KB	Output is correct
22	Correct	56 ms	96344 KB	Output is correct
23	Correct	66 ms	96344 KB	Output is correct
24	Execution timed out	4011 ms	96344 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	23804 KB	Output is correct
2	Correct	24 ms	24052 KB	Output is correct
3	Correct	25 ms	24276 KB	Output is correct
4	Correct	24 ms	24276 KB	Output is correct
5	Correct	23 ms	24276 KB	Output is correct
6	Correct	24 ms	24496 KB	Output is correct
7	Correct	22 ms	24496 KB	Output is correct
8	Correct	24 ms	24496 KB	Output is correct
9	Correct	27 ms	24496 KB	Output is correct
10	Correct	24 ms	24496 KB	Output is correct
11	Correct	463 ms	46664 KB	Output is correct
12	Correct	955 ms	58536 KB	Output is correct
13	Correct	1223 ms	62648 KB	Output is correct
14	Correct	1195 ms	67280 KB	Output is correct
15	Correct	1221 ms	68520 KB	Output is correct
16	Correct	1300 ms	96344 KB	Output is correct
17	Correct	1106 ms	96344 KB	Output is correct
18	Correct	1157 ms	96344 KB	Output is correct
19	Correct	1319 ms	96344 KB	Output is correct
20	Correct	879 ms	96344 KB	Output is correct
21	Correct	25 ms	96344 KB	Output is correct
22	Correct	30 ms	96344 KB	Output is correct
23	Correct	29 ms	96344 KB	Output is correct
24	Correct	35 ms	96344 KB	Output is correct
25	Correct	28 ms	96344 KB	Output is correct
26	Correct	29 ms	96344 KB	Output is correct
27	Correct	27 ms	96344 KB	Output is correct
28	Correct	38 ms	96344 KB	Output is correct
29	Correct	29 ms	96344 KB	Output is correct
30	Correct	34 ms	96344 KB	Output is correct
31	Correct	44 ms	96344 KB	Output is correct
32	Correct	56 ms	96344 KB	Output is correct
33	Correct	66 ms	96344 KB	Output is correct
34	Execution timed out	4011 ms	96344 KB	Time limit exceeded
35	Halted	0 ms	0 KB	-

답안 #66457

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