/*************************************
* author: marvinthang *
* created: 06.05.2024 15:52:23 *
*************************************/
#include <bits/stdc++.h>
using namespace std;
#define fi first
#define se second
#define left ___left
#define right ___right
#define TIME (1.0 * clock() / CLOCKS_PER_SEC)
#define MASK(i) (1LL << (i))
#define BIT(x, i) ((x) >> (i) & 1)
#define __builtin_popcount __builtin_popcountll
#define ALL(v) (v).begin(), (v).end()
#define REP(i, n) for (int i = 0, _n = (n); i < _n; ++i)
#define REPD(i, n) for (int i = (n); i-- > 0; )
#define FOR(i, a, b) for (int i = (a), _b = (b); i < _b; ++i)
#define FORD(i, b, a) for (int i = (b), _a = (a); --i >= _a; )
#define FORE(i, a, b) for (int i = (a), _b = (b); i <= _b; ++i)
#define FORDE(i, b, a) for (int i = (b), _a = (a); i >= _a; --i)
#define scan_op(...) istream & operator >> (istream &in, __VA_ARGS__ &u)
#define print_op(...) ostream & operator << (ostream &out, const __VA_ARGS__ &u)
#ifdef LOCAL
#include "debug.h"
#else
#define file(name) if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
#define DB(...) 23
#define db(...) 23
#define debug(...) 23
#endif
template <class U, class V> scan_op(pair <U, V>) { return in >> u.first >> u.second; }
template <class T> scan_op(vector <T>) { for (size_t i = 0; i < u.size(); ++i) in >> u[i]; return in; }
template <class U, class V> print_op(pair <U, V>) { return out << '(' << u.first << ", " << u.second << ')'; }
template <size_t i, class T> ostream & print_tuple_utils(ostream &out, const T &tup) { if constexpr(i == tuple_size<T>::value) return out << ")"; else return print_tuple_utils<i + 1, T>(out << (i ? ", " : "(") << get<i>(tup), tup); }
template <class ...U> print_op(tuple<U...>) { return print_tuple_utils<0, tuple<U...>>(out, u); }
template <class Con, class = decltype(begin(declval<Con>()))> typename enable_if <!is_same<Con, string>::value, ostream&>::type operator << (ostream &out, const Con &con) { out << '{'; for (__typeof(con.begin()) it = con.begin(); it != con.end(); ++it) out << (it == con.begin() ? "" : ", ") << *it; return out << '}'; }
// end of template
const int LOG = 19;
void process(void) {
int n, m; cin >> n >> m;
vector <pair <int, int>> a(n); cin >> a;
vector <int> c;
REP(i, n) {
c.push_back(a[i].fi);
c.push_back(a[i].se);
}
sort(ALL(c));
c.erase(unique(ALL(c)), c.end());
REP(i, n) {
a[i].fi = lower_bound(ALL(c), a[i].fi) - c.begin();
a[i].se = lower_bound(ALL(c), a[i].se) - c.begin();
if (a[i].fi > a[i].se) a[i].se += c.size();
a.emplace_back(a[i].fi + c.size(), a[i].se + c.size());
}
n += n;
sort(ALL(a));
vector <array <pair <int, int>, LOG>> ma(n);
REP(i, n) ma[i][0] = pair{a[i].se, i};
FOR(k, 1, LOG) REP(i, n - MASK(k) + 1) ma[i][k] = max(ma[i][k - 1], ma[i + MASK(k - 1)][k - 1]);
auto get_max = [&] (int l, int r) {
if (l > r) return n;
int h = __lg(r - l + 1);
return max(ma[l][h], ma[r - MASK(h) + 1][h]).se;
};
vector <array <int, LOG>> nxt(n + 1);
nxt[n][0] = n;
REP(i, n) {
int pos = lower_bound(i + ALL(a), pair{a[i].se + 1, -1}) - a.begin() - 1;
nxt[i][0] = get_max(i + 1, pos);
}
FOR(k, 1, LOG) REP(i, n + 1) nxt[i][k] = nxt[nxt[i][k - 1]][k - 1];
int res = n + 1;
REP(i, n / 2) {
int cur = 0, u = i;
REPD(j, LOG) if (nxt[u][j] < n && a[nxt[u][j]].se < a[i].fi + c.size()) {
u = nxt[u][j];
cur ^= MASK(j);
}
if (nxt[u][0] < n) res = min(res, cur + 2);
}
cout << (res == n + 1 ? -1 : res) << '\n';
}
int main(void) {
ios_base::sync_with_stdio(false); cin.tie(nullptr); // cout.tie(nullptr);
file("fire");
// int t; cin >> t; while (t--)
process();
// cerr << "Time elapsed: " << TIME << " s.\n";
return (0^0);
}
Compilation message
Main.cpp: In function 'void process()':
Main.cpp:83:53: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
83 | REPD(j, LOG) if (nxt[u][j] < n && a[nxt[u][j]].se < a[i].fi + c.size()) {
Main.cpp: In function 'int main()':
Main.cpp:30:61: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
30 | #define file(name) if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:94:2: note: in expansion of macro 'file'
94 | file("fire");
| ^~~~
Main.cpp:30:94: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
30 | #define file(name) if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:94:2: note: in expansion of macro 'file'
94 | file("fire");
| ^~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
604 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
0 ms |
348 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
5 |
Correct |
0 ms |
348 KB |
Output is correct |
6 |
Correct |
0 ms |
348 KB |
Output is correct |
7 |
Correct |
0 ms |
348 KB |
Output is correct |
8 |
Correct |
0 ms |
348 KB |
Output is correct |
9 |
Correct |
0 ms |
348 KB |
Output is correct |
10 |
Correct |
0 ms |
348 KB |
Output is correct |
11 |
Correct |
0 ms |
348 KB |
Output is correct |
12 |
Correct |
0 ms |
348 KB |
Output is correct |
13 |
Correct |
0 ms |
452 KB |
Output is correct |
14 |
Correct |
0 ms |
468 KB |
Output is correct |
15 |
Correct |
1 ms |
348 KB |
Output is correct |
16 |
Correct |
0 ms |
348 KB |
Output is correct |
17 |
Correct |
0 ms |
348 KB |
Output is correct |
18 |
Correct |
0 ms |
348 KB |
Output is correct |
19 |
Correct |
0 ms |
348 KB |
Output is correct |
20 |
Correct |
1 ms |
348 KB |
Output is correct |
21 |
Correct |
1 ms |
452 KB |
Output is correct |
22 |
Correct |
0 ms |
348 KB |
Output is correct |
23 |
Correct |
0 ms |
348 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
604 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
0 ms |
348 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
5 |
Correct |
0 ms |
348 KB |
Output is correct |
6 |
Correct |
0 ms |
348 KB |
Output is correct |
7 |
Correct |
0 ms |
348 KB |
Output is correct |
8 |
Correct |
0 ms |
348 KB |
Output is correct |
9 |
Correct |
0 ms |
348 KB |
Output is correct |
10 |
Correct |
0 ms |
348 KB |
Output is correct |
11 |
Correct |
0 ms |
348 KB |
Output is correct |
12 |
Correct |
0 ms |
348 KB |
Output is correct |
13 |
Correct |
0 ms |
452 KB |
Output is correct |
14 |
Correct |
0 ms |
468 KB |
Output is correct |
15 |
Correct |
1 ms |
348 KB |
Output is correct |
16 |
Correct |
0 ms |
348 KB |
Output is correct |
17 |
Correct |
0 ms |
348 KB |
Output is correct |
18 |
Correct |
0 ms |
348 KB |
Output is correct |
19 |
Correct |
0 ms |
348 KB |
Output is correct |
20 |
Correct |
1 ms |
348 KB |
Output is correct |
21 |
Correct |
1 ms |
452 KB |
Output is correct |
22 |
Correct |
0 ms |
348 KB |
Output is correct |
23 |
Correct |
0 ms |
348 KB |
Output is correct |
24 |
Correct |
0 ms |
348 KB |
Output is correct |
25 |
Correct |
0 ms |
604 KB |
Output is correct |
26 |
Correct |
1 ms |
604 KB |
Output is correct |
27 |
Correct |
0 ms |
588 KB |
Output is correct |
28 |
Correct |
1 ms |
604 KB |
Output is correct |
29 |
Correct |
1 ms |
604 KB |
Output is correct |
30 |
Correct |
1 ms |
604 KB |
Output is correct |
31 |
Correct |
1 ms |
604 KB |
Output is correct |
32 |
Correct |
1 ms |
604 KB |
Output is correct |
33 |
Correct |
0 ms |
604 KB |
Output is correct |
34 |
Correct |
1 ms |
604 KB |
Output is correct |
35 |
Correct |
1 ms |
604 KB |
Output is correct |
36 |
Correct |
1 ms |
456 KB |
Output is correct |
37 |
Correct |
0 ms |
588 KB |
Output is correct |
38 |
Correct |
0 ms |
604 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
604 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
0 ms |
348 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
5 |
Correct |
0 ms |
348 KB |
Output is correct |
6 |
Correct |
0 ms |
348 KB |
Output is correct |
7 |
Correct |
0 ms |
348 KB |
Output is correct |
8 |
Correct |
0 ms |
348 KB |
Output is correct |
9 |
Correct |
0 ms |
348 KB |
Output is correct |
10 |
Correct |
0 ms |
348 KB |
Output is correct |
11 |
Correct |
0 ms |
348 KB |
Output is correct |
12 |
Correct |
0 ms |
348 KB |
Output is correct |
13 |
Correct |
0 ms |
452 KB |
Output is correct |
14 |
Correct |
0 ms |
468 KB |
Output is correct |
15 |
Correct |
1 ms |
348 KB |
Output is correct |
16 |
Correct |
0 ms |
348 KB |
Output is correct |
17 |
Correct |
0 ms |
348 KB |
Output is correct |
18 |
Correct |
0 ms |
348 KB |
Output is correct |
19 |
Correct |
0 ms |
348 KB |
Output is correct |
20 |
Correct |
1 ms |
348 KB |
Output is correct |
21 |
Correct |
1 ms |
452 KB |
Output is correct |
22 |
Correct |
0 ms |
348 KB |
Output is correct |
23 |
Correct |
0 ms |
348 KB |
Output is correct |
24 |
Correct |
0 ms |
348 KB |
Output is correct |
25 |
Correct |
0 ms |
604 KB |
Output is correct |
26 |
Correct |
1 ms |
604 KB |
Output is correct |
27 |
Correct |
0 ms |
588 KB |
Output is correct |
28 |
Correct |
1 ms |
604 KB |
Output is correct |
29 |
Correct |
1 ms |
604 KB |
Output is correct |
30 |
Correct |
1 ms |
604 KB |
Output is correct |
31 |
Correct |
1 ms |
604 KB |
Output is correct |
32 |
Correct |
1 ms |
604 KB |
Output is correct |
33 |
Correct |
0 ms |
604 KB |
Output is correct |
34 |
Correct |
1 ms |
604 KB |
Output is correct |
35 |
Correct |
1 ms |
604 KB |
Output is correct |
36 |
Correct |
1 ms |
456 KB |
Output is correct |
37 |
Correct |
0 ms |
588 KB |
Output is correct |
38 |
Correct |
0 ms |
604 KB |
Output is correct |
39 |
Correct |
5 ms |
2904 KB |
Output is correct |
40 |
Correct |
5 ms |
3032 KB |
Output is correct |
41 |
Correct |
5 ms |
2908 KB |
Output is correct |
42 |
Correct |
4 ms |
2796 KB |
Output is correct |
43 |
Correct |
4 ms |
2908 KB |
Output is correct |
44 |
Correct |
4 ms |
2908 KB |
Output is correct |
45 |
Correct |
5 ms |
2904 KB |
Output is correct |
46 |
Correct |
4 ms |
2908 KB |
Output is correct |
47 |
Correct |
4 ms |
2908 KB |
Output is correct |
48 |
Correct |
6 ms |
2908 KB |
Output is correct |
49 |
Correct |
4 ms |
2908 KB |
Output is correct |
50 |
Correct |
5 ms |
2912 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
0 ms |
348 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
5 |
Correct |
0 ms |
456 KB |
Output is correct |
6 |
Correct |
0 ms |
344 KB |
Output is correct |
7 |
Correct |
0 ms |
348 KB |
Output is correct |
8 |
Correct |
1 ms |
456 KB |
Output is correct |
9 |
Correct |
0 ms |
604 KB |
Output is correct |
10 |
Correct |
1 ms |
604 KB |
Output is correct |
11 |
Correct |
0 ms |
604 KB |
Output is correct |
12 |
Correct |
0 ms |
604 KB |
Output is correct |
13 |
Correct |
0 ms |
604 KB |
Output is correct |
14 |
Correct |
1 ms |
460 KB |
Output is correct |
15 |
Correct |
5 ms |
2908 KB |
Output is correct |
16 |
Correct |
4 ms |
2772 KB |
Output is correct |
17 |
Correct |
5 ms |
2908 KB |
Output is correct |
18 |
Correct |
4 ms |
2908 KB |
Output is correct |
19 |
Correct |
5 ms |
2896 KB |
Output is correct |
20 |
Correct |
145 ms |
95136 KB |
Output is correct |
21 |
Correct |
265 ms |
98428 KB |
Output is correct |
22 |
Correct |
267 ms |
98264 KB |
Output is correct |
23 |
Correct |
233 ms |
97188 KB |
Output is correct |
24 |
Correct |
238 ms |
98352 KB |
Output is correct |
25 |
Correct |
255 ms |
97548 KB |
Output is correct |
26 |
Correct |
235 ms |
98336 KB |
Output is correct |
27 |
Correct |
226 ms |
98208 KB |
Output is correct |
28 |
Correct |
248 ms |
98216 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
348 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
0 ms |
348 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
5 |
Correct |
1 ms |
604 KB |
Output is correct |
6 |
Correct |
0 ms |
348 KB |
Output is correct |
7 |
Correct |
0 ms |
348 KB |
Output is correct |
8 |
Correct |
0 ms |
604 KB |
Output is correct |
9 |
Correct |
0 ms |
604 KB |
Output is correct |
10 |
Correct |
0 ms |
604 KB |
Output is correct |
11 |
Correct |
0 ms |
604 KB |
Output is correct |
12 |
Correct |
6 ms |
2908 KB |
Output is correct |
13 |
Correct |
5 ms |
2908 KB |
Output is correct |
14 |
Correct |
4 ms |
2908 KB |
Output is correct |
15 |
Correct |
136 ms |
95248 KB |
Output is correct |
16 |
Correct |
214 ms |
97456 KB |
Output is correct |
17 |
Correct |
250 ms |
98340 KB |
Output is correct |
18 |
Correct |
230 ms |
98172 KB |
Output is correct |
19 |
Correct |
236 ms |
98184 KB |
Output is correct |
20 |
Correct |
220 ms |
97232 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
604 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
0 ms |
348 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
5 |
Correct |
0 ms |
348 KB |
Output is correct |
6 |
Correct |
0 ms |
348 KB |
Output is correct |
7 |
Correct |
0 ms |
348 KB |
Output is correct |
8 |
Correct |
0 ms |
348 KB |
Output is correct |
9 |
Correct |
0 ms |
348 KB |
Output is correct |
10 |
Correct |
0 ms |
348 KB |
Output is correct |
11 |
Correct |
0 ms |
348 KB |
Output is correct |
12 |
Correct |
0 ms |
348 KB |
Output is correct |
13 |
Correct |
0 ms |
452 KB |
Output is correct |
14 |
Correct |
0 ms |
468 KB |
Output is correct |
15 |
Correct |
1 ms |
348 KB |
Output is correct |
16 |
Correct |
0 ms |
348 KB |
Output is correct |
17 |
Correct |
0 ms |
348 KB |
Output is correct |
18 |
Correct |
0 ms |
348 KB |
Output is correct |
19 |
Correct |
0 ms |
348 KB |
Output is correct |
20 |
Correct |
1 ms |
348 KB |
Output is correct |
21 |
Correct |
1 ms |
452 KB |
Output is correct |
22 |
Correct |
0 ms |
348 KB |
Output is correct |
23 |
Correct |
0 ms |
348 KB |
Output is correct |
24 |
Correct |
0 ms |
348 KB |
Output is correct |
25 |
Correct |
0 ms |
604 KB |
Output is correct |
26 |
Correct |
1 ms |
604 KB |
Output is correct |
27 |
Correct |
0 ms |
588 KB |
Output is correct |
28 |
Correct |
1 ms |
604 KB |
Output is correct |
29 |
Correct |
1 ms |
604 KB |
Output is correct |
30 |
Correct |
1 ms |
604 KB |
Output is correct |
31 |
Correct |
1 ms |
604 KB |
Output is correct |
32 |
Correct |
1 ms |
604 KB |
Output is correct |
33 |
Correct |
0 ms |
604 KB |
Output is correct |
34 |
Correct |
1 ms |
604 KB |
Output is correct |
35 |
Correct |
1 ms |
604 KB |
Output is correct |
36 |
Correct |
1 ms |
456 KB |
Output is correct |
37 |
Correct |
0 ms |
588 KB |
Output is correct |
38 |
Correct |
0 ms |
604 KB |
Output is correct |
39 |
Correct |
5 ms |
2904 KB |
Output is correct |
40 |
Correct |
5 ms |
3032 KB |
Output is correct |
41 |
Correct |
5 ms |
2908 KB |
Output is correct |
42 |
Correct |
4 ms |
2796 KB |
Output is correct |
43 |
Correct |
4 ms |
2908 KB |
Output is correct |
44 |
Correct |
4 ms |
2908 KB |
Output is correct |
45 |
Correct |
5 ms |
2904 KB |
Output is correct |
46 |
Correct |
4 ms |
2908 KB |
Output is correct |
47 |
Correct |
4 ms |
2908 KB |
Output is correct |
48 |
Correct |
6 ms |
2908 KB |
Output is correct |
49 |
Correct |
4 ms |
2908 KB |
Output is correct |
50 |
Correct |
5 ms |
2912 KB |
Output is correct |
51 |
Correct |
0 ms |
348 KB |
Output is correct |
52 |
Correct |
0 ms |
348 KB |
Output is correct |
53 |
Correct |
0 ms |
348 KB |
Output is correct |
54 |
Correct |
0 ms |
348 KB |
Output is correct |
55 |
Correct |
0 ms |
456 KB |
Output is correct |
56 |
Correct |
0 ms |
344 KB |
Output is correct |
57 |
Correct |
0 ms |
348 KB |
Output is correct |
58 |
Correct |
1 ms |
456 KB |
Output is correct |
59 |
Correct |
0 ms |
604 KB |
Output is correct |
60 |
Correct |
1 ms |
604 KB |
Output is correct |
61 |
Correct |
0 ms |
604 KB |
Output is correct |
62 |
Correct |
0 ms |
604 KB |
Output is correct |
63 |
Correct |
0 ms |
604 KB |
Output is correct |
64 |
Correct |
1 ms |
460 KB |
Output is correct |
65 |
Correct |
5 ms |
2908 KB |
Output is correct |
66 |
Correct |
4 ms |
2772 KB |
Output is correct |
67 |
Correct |
5 ms |
2908 KB |
Output is correct |
68 |
Correct |
4 ms |
2908 KB |
Output is correct |
69 |
Correct |
5 ms |
2896 KB |
Output is correct |
70 |
Correct |
145 ms |
95136 KB |
Output is correct |
71 |
Correct |
265 ms |
98428 KB |
Output is correct |
72 |
Correct |
267 ms |
98264 KB |
Output is correct |
73 |
Correct |
233 ms |
97188 KB |
Output is correct |
74 |
Correct |
238 ms |
98352 KB |
Output is correct |
75 |
Correct |
255 ms |
97548 KB |
Output is correct |
76 |
Correct |
235 ms |
98336 KB |
Output is correct |
77 |
Correct |
226 ms |
98208 KB |
Output is correct |
78 |
Correct |
248 ms |
98216 KB |
Output is correct |
79 |
Correct |
1 ms |
348 KB |
Output is correct |
80 |
Correct |
0 ms |
348 KB |
Output is correct |
81 |
Correct |
0 ms |
348 KB |
Output is correct |
82 |
Correct |
0 ms |
348 KB |
Output is correct |
83 |
Correct |
1 ms |
604 KB |
Output is correct |
84 |
Correct |
0 ms |
348 KB |
Output is correct |
85 |
Correct |
0 ms |
348 KB |
Output is correct |
86 |
Correct |
0 ms |
604 KB |
Output is correct |
87 |
Correct |
0 ms |
604 KB |
Output is correct |
88 |
Correct |
0 ms |
604 KB |
Output is correct |
89 |
Correct |
0 ms |
604 KB |
Output is correct |
90 |
Correct |
6 ms |
2908 KB |
Output is correct |
91 |
Correct |
5 ms |
2908 KB |
Output is correct |
92 |
Correct |
4 ms |
2908 KB |
Output is correct |
93 |
Correct |
136 ms |
95248 KB |
Output is correct |
94 |
Correct |
214 ms |
97456 KB |
Output is correct |
95 |
Correct |
250 ms |
98340 KB |
Output is correct |
96 |
Correct |
230 ms |
98172 KB |
Output is correct |
97 |
Correct |
236 ms |
98184 KB |
Output is correct |
98 |
Correct |
220 ms |
97232 KB |
Output is correct |
99 |
Correct |
269 ms |
98216 KB |
Output is correct |
100 |
Correct |
274 ms |
98316 KB |
Output is correct |
101 |
Correct |
226 ms |
98220 KB |
Output is correct |
102 |
Correct |
262 ms |
98212 KB |
Output is correct |
103 |
Correct |
260 ms |
98352 KB |
Output is correct |
104 |
Correct |
280 ms |
98180 KB |
Output is correct |
105 |
Correct |
207 ms |
96932 KB |
Output is correct |