답안 #884290

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
884290	2023-12-07T06:03:11 Z	Kevin_Zhang_TW	Parking (CEOI22_parking)	C++17	100 / 100	226 ms	34760 KB

Main

#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define pb emplace_back
#define AI(i) begin(i), end(i)
template<class T> bool chmin(T &a, T b) { return b < a && (a = b, true); }
template<class T> bool chmax(T &a, T b) { return a < b && (a = b, true); }
#ifdef KEV
#define DE(args...) kout("[ " + string(#args) + " ] = ", args)
void kout() { cerr << endl; }
template<class T, class ...U> void kout(T a, U ...b) { cerr << a << ' ', kout(b...); }
template<class T> void debug(T l, T r) { while (l != r) cerr << *l << " \n"[next(l)==r], ++l; }
#else
#define DE(...) 0
#define debug(...) 0
#endif
// My bug list :
// integer overflow
// 0based, 1based forgotten
// index out of bound
// n, m, i, j typo
// some cases are missing

const int MAX_N = 300010;

int n, m;
vector<int> stk[MAX_N], emp;
vector<int> at[MAX_N];
void fail() {
  cout << -1 << '\n';
  exit(0);
}
int32_t main() {
  ios_base::sync_with_stdio(0), cin.tie(0);
  cin >> n >> m;
  for (int i = 0;i < m;++i) {
    int b, t;
    cin >> b >> t;
    for (int j : {b, t}) if (j) {
      stk[i].pb(j);
      at[j].pb(i);
    }
    if (b == 0) emp.pb(i);
  }

  vector<pair<int,int>> res;
  // all full or empty
//
//  vector<pair<int,int>> ud;
  auto hp = [&]() {
    DE("stk");
    for (int i = 0;i < m;++i)
      debug(AI(stk[i]));
  };
  auto atob = [&](int a, int b) {
    int v = stk[a].back(); stk[a].pop_back();
    stk[b].pb(v);
    *find(AI(at[v]), a) = b;
    res.pb(a, b);
  };
  auto other = [&](int x, int p) {
    return at[x][0] + at[x][1] - p;
  };
  auto shift = [&](int p) {
    assert(stk[p].size() == 1);
    int v = stk[p][0], o = other(v, p);
    while (stk[o].size() == 2 && stk[o][1] == v) {
      atob(o, p);
      p = o;
      v = stk[p][0];
      o = other(v, p);
    }
    return p;
  };
  auto eqtop = [&](int p) {
    int v = stk[p][1], o = other(v, p);
    while (stk[o][0] == v) {
      p = o;
      v = stk[p][1], o = other(v, p);
    }
    return p;
  };
  function<void(int)> take_care = [&](int p) {
    if (emp.empty()) fail();
    if (stk[p].empty()) {
      emp.pb(p);
      return;
    }
    assert(stk[p].size() == 1);
    int v = stk[p][0];
    int e = emp.back(), o = other(v, p);
    if (stk[o].size() == 1 || stk[o][1] == v) {
      atob(o, p);
      take_care(o);
      return;
    }
    int g = eqtop(o);
    atob(g, e);
    shift(g);
    atob(o, p);
    emp.back() = o;
    take_care(e);
  };

  function<void(int)> no_more_care = [&](int p) {
    if (stk[p].empty()) {
      emp.pb(p);
      return;
    }
    assert(stk[p].size() == 1);
    int v = stk[p][0];
    int o = other(v, p);
    if (stk[o].back() == v) {
      atob(o, p);
      no_more_care(o);
    }
  };

  for (int i = 0;i < m;++i) if (stk[i].size() == 1) {
    no_more_care(i);
  }
  //hp();
  for (int i = 0;i < m;++i) if (stk[i].size() == 1)
    take_care(i);
//    int x = stk[i][0];
//    if (stk[other(x, i)].back() == x)
//      take_
  for (int i = 1;i <= n;++i) {
    int a = at[i][0], b = at[i][1];
    if (a == b) continue;
    if (stk[a].size() + stk[b].size() == 4 && 
      stk[a].back() == i && stk[b].back() == i) {
      if (emp.empty()) fail();
      int e = emp.back(); emp.pop_back();
      atob(a, e);
      atob(b, e);
      a = shift(a), b = shift(b);
      if (stk[a][0] == stk[b][0]) {
        atob(a, b);
        emp.pb(a);
      } else {
        take_care(a);
      }
    }
  }

  for (int i = 1;i <= n;++i) {
    int a = at[i][0], b = at[i][1];
    if (a == b) continue;
    if (emp.empty()) fail();
    if (stk[a][0] != i) swap(a, b);
    // stk[a][0] = i
    int e = emp.back();
    atob(a, e);
    int g = shift(a);
    atob(e, g);
    // must be one up and one down
  }
  for (int i = 1;i <= n;++i) assert(at[i][0] == at[i][1]);

  cout << res.size() << '\n';
  for (auto [a, b] : res) {
    ++a, ++b;
    cout << a << ' ' << b << '\n';
  }
}

Compilation message

Main.cpp: In lambda function:
Main.cpp:14:17: warning: statement has no effect [-Wunused-value]
   14 | #define DE(...) 0
      |                 ^
Main.cpp:51:5: note: in expansion of macro 'DE'
   51 |     DE("stk");
      |     ^~
Main.cpp:15:20: warning: statement has no effect [-Wunused-value]
   15 | #define debug(...) 0
      |                    ^
Main.cpp:53:7: note: in expansion of macro 'debug'
   53 |       debug(AI(stk[i]));
      |       ^~~~~
Main.cpp: In function 'int32_t main()':
Main.cpp:50:8: warning: variable 'hp' set but not used [-Wunused-but-set-variable]
   50 |   auto hp = [&]() {
      |        ^~

Subtask #1

10.0 / 10.0

#	결과	실행 시간	메모리	Grader output
1	Correct	5 ms	14424 KB	Output is correct
2	Correct	3 ms	14536 KB	Output is correct
3	Correct	3 ms	14424 KB	Output is correct
4	Correct	4 ms	14428 KB	Output is correct
5	Correct	4 ms	14424 KB	Output is correct
6	Correct	4 ms	14428 KB	Output is correct
7	Correct	4 ms	14428 KB	Output is correct
8	Correct	3 ms	14428 KB	Output is correct
9	Correct	3 ms	14424 KB	Output is correct
10	Correct	3 ms	14428 KB	Output is correct

Subtask #2

10.0 / 10.0

#	결과	실행 시간	메모리	Grader output
1	Correct	75 ms	23112 KB	Output is correct
2	Correct	112 ms	26164 KB	Output is correct
3	Correct	65 ms	22336 KB	Output is correct
4	Correct	59 ms	22328 KB	Output is correct
5	Correct	100 ms	25928 KB	Output is correct

Subtask #3

25.0 / 25.0

#	결과	실행 시간	메모리	Grader output
1	Correct	4 ms	14424 KB	Output is correct
2	Correct	4 ms	14424 KB	Output is correct
3	Correct	4 ms	14424 KB	Output is correct
4	Correct	4 ms	14624 KB	Output is correct
5	Correct	5 ms	14428 KB	Output is correct
6	Correct	4 ms	14424 KB	Output is correct
7	Correct	5 ms	14424 KB	Output is correct
8	Correct	4 ms	14424 KB	Output is correct
9	Correct	4 ms	14428 KB	Output is correct

Subtask #4

15.0 / 15.0

#	결과	실행 시간	메모리	Grader output
1	Correct	4 ms	14424 KB	Output is correct
2	Correct	4 ms	14424 KB	Output is correct
3	Correct	4 ms	14424 KB	Output is correct
4	Correct	4 ms	14624 KB	Output is correct
5	Correct	5 ms	14428 KB	Output is correct
6	Correct	4 ms	14424 KB	Output is correct
7	Correct	5 ms	14424 KB	Output is correct
8	Correct	4 ms	14424 KB	Output is correct
9	Correct	4 ms	14428 KB	Output is correct
10	Correct	176 ms	31908 KB	Output is correct
11	Correct	66 ms	26628 KB	Output is correct
12	Correct	95 ms	26616 KB	Output is correct
13	Correct	160 ms	30948 KB	Output is correct
14	Correct	78 ms	26964 KB	Output is correct
15	Correct	88 ms	26488 KB	Output is correct
16	Correct	207 ms	32196 KB	Output is correct
17	Correct	74 ms	26388 KB	Output is correct
18	Correct	155 ms	31684 KB	Output is correct

Subtask #5

25.0 / 25.0

#	결과	실행 시간	메모리	Grader output
1	Correct	4 ms	14424 KB	Output is correct
2	Correct	5 ms	14428 KB	Output is correct
3	Correct	4 ms	14424 KB	Output is correct
4	Correct	3 ms	14424 KB	Output is correct
5	Correct	5 ms	14560 KB	Output is correct
6	Correct	4 ms	14424 KB	Output is correct
7	Correct	4 ms	14428 KB	Output is correct
8	Correct	4 ms	14424 KB	Output is correct
9	Correct	4 ms	14428 KB	Output is correct
10	Correct	4 ms	14428 KB	Output is correct
11	Correct	4 ms	14428 KB	Output is correct
12	Correct	4 ms	14424 KB	Output is correct
13	Correct	4 ms	14428 KB	Output is correct
14	Correct	4 ms	14428 KB	Output is correct
15	Correct	4 ms	14424 KB	Output is correct
16	Correct	4 ms	14428 KB	Output is correct
17	Correct	3 ms	14424 KB	Output is correct
18	Correct	4 ms	14428 KB	Output is correct
19	Correct	4 ms	14428 KB	Output is correct
20	Correct	4 ms	14428 KB	Output is correct
21	Correct	4 ms	14532 KB	Output is correct
22	Correct	4 ms	14428 KB	Output is correct
23	Correct	4 ms	14428 KB	Output is correct
24	Correct	4 ms	14424 KB	Output is correct

Subtask #6

15.0 / 15.0

#	결과	실행 시간	메모리	Grader output
1	Correct	5 ms	14424 KB	Output is correct
2	Correct	3 ms	14536 KB	Output is correct
3	Correct	3 ms	14424 KB	Output is correct
4	Correct	4 ms	14428 KB	Output is correct
5	Correct	4 ms	14424 KB	Output is correct
6	Correct	4 ms	14428 KB	Output is correct
7	Correct	4 ms	14428 KB	Output is correct
8	Correct	3 ms	14428 KB	Output is correct
9	Correct	3 ms	14424 KB	Output is correct
10	Correct	3 ms	14428 KB	Output is correct
11	Correct	75 ms	23112 KB	Output is correct
12	Correct	112 ms	26164 KB	Output is correct
13	Correct	65 ms	22336 KB	Output is correct
14	Correct	59 ms	22328 KB	Output is correct
15	Correct	100 ms	25928 KB	Output is correct
16	Correct	4 ms	14424 KB	Output is correct
17	Correct	4 ms	14424 KB	Output is correct
18	Correct	4 ms	14424 KB	Output is correct
19	Correct	4 ms	14624 KB	Output is correct
20	Correct	5 ms	14428 KB	Output is correct
21	Correct	4 ms	14424 KB	Output is correct
22	Correct	5 ms	14424 KB	Output is correct
23	Correct	4 ms	14424 KB	Output is correct
24	Correct	4 ms	14428 KB	Output is correct
25	Correct	176 ms	31908 KB	Output is correct
26	Correct	66 ms	26628 KB	Output is correct
27	Correct	95 ms	26616 KB	Output is correct
28	Correct	160 ms	30948 KB	Output is correct
29	Correct	78 ms	26964 KB	Output is correct
30	Correct	88 ms	26488 KB	Output is correct
31	Correct	207 ms	32196 KB	Output is correct
32	Correct	74 ms	26388 KB	Output is correct
33	Correct	155 ms	31684 KB	Output is correct
34	Correct	4 ms	14424 KB	Output is correct
35	Correct	5 ms	14428 KB	Output is correct
36	Correct	4 ms	14424 KB	Output is correct
37	Correct	3 ms	14424 KB	Output is correct
38	Correct	5 ms	14560 KB	Output is correct
39	Correct	4 ms	14424 KB	Output is correct
40	Correct	4 ms	14428 KB	Output is correct
41	Correct	4 ms	14424 KB	Output is correct
42	Correct	4 ms	14428 KB	Output is correct
43	Correct	4 ms	14428 KB	Output is correct
44	Correct	4 ms	14428 KB	Output is correct
45	Correct	4 ms	14424 KB	Output is correct
46	Correct	4 ms	14428 KB	Output is correct
47	Correct	4 ms	14428 KB	Output is correct
48	Correct	4 ms	14424 KB	Output is correct
49	Correct	4 ms	14428 KB	Output is correct
50	Correct	3 ms	14424 KB	Output is correct
51	Correct	4 ms	14428 KB	Output is correct
52	Correct	4 ms	14428 KB	Output is correct
53	Correct	4 ms	14428 KB	Output is correct
54	Correct	4 ms	14532 KB	Output is correct
55	Correct	4 ms	14428 KB	Output is correct
56	Correct	4 ms	14428 KB	Output is correct
57	Correct	4 ms	14424 KB	Output is correct
58	Correct	174 ms	32780 KB	Output is correct
59	Correct	177 ms	34692 KB	Output is correct
60	Correct	134 ms	31288 KB	Output is correct
61	Correct	142 ms	32856 KB	Output is correct
62	Correct	71 ms	29468 KB	Output is correct
63	Correct	216 ms	32960 KB	Output is correct
64	Correct	77 ms	29264 KB	Output is correct
65	Correct	188 ms	33704 KB	Output is correct
66	Correct	169 ms	34760 KB	Output is correct
67	Correct	78 ms	28768 KB	Output is correct
68	Correct	226 ms	33468 KB	Output is correct
69	Correct	169 ms	32964 KB	Output is correct
70	Correct	75 ms	28680 KB	Output is correct
71	Correct	80 ms	29268 KB	Output is correct
72	Correct	72 ms	29092 KB	Output is correct
73	Correct	160 ms	34632 KB	Output is correct
74	Correct	77 ms	29000 KB	Output is correct
75	Correct	181 ms	34160 KB	Output is correct
76	Correct	159 ms	34428 KB	Output is correct
77	Correct	192 ms	33980 KB	Output is correct
78	Correct	115 ms	29228 KB	Output is correct
79	Correct	177 ms	33916 KB	Output is correct
80	Correct	74 ms	28848 KB	Output is correct
81	Correct	150 ms	34040 KB	Output is correct