oj.uz

답안 #20503

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
20503 2017-02-12T07:00:49 Z admin 초음속철도 (OJUZ11_rail) C++14
0 / 100
 189 ms 28580 KB 
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <memory.h>
#include <math.h>
#include <assert.h>
#include <stack>
#include <queue>
#include <map>
#include <set>
#include <algorithm>
#include <string>
#include <functional>
#include <vector>
#include <deque>
#include <utility>
#include <bitset>
#include <limits.h>
#include <time.h>
#include <functional>
#include <numeric>

using namespace std;
typedef long long ll;
typedef unsigned long long llu;
typedef double lf;
typedef unsigned int uint;
typedef long double llf;
typedef pair<int, int> pii;
typedef pair<ll, int> pli;

#define debug(format, ...) printf(format, __VA_ARGS__);

const int N_ = 500500;
const int M_ = 500500;

const int MOD = (ll)1e9 + 7;

class modint {
	int v;
public:
	modint (): v(0) { }
	modint (ll v): v((v + MOD) % MOD) { }

	bool operator== (modint x) { return v == x.v; }
	bool operator!= (modint x) { return v != x.v; }

	modint operator+ (modint x) { return v + x.v; }
	modint operator- (modint x) { return v - x.v; }
	modint operator* (modint x) { return (ll)v * x.v; }

	modint& operator+= (const modint x) { return *this = (*this + x); }
	modint& operator-= (const modint x) { return *this = (*this - x); }
	modint& operator*= (const modint x) { return *this = (*this * x); }

	int operator* () { return v; }
};

int N, M;
vector< pair<int, int> > intervals;
int F;
vector< int* > renum;

int main() {
	assert(scanf("%d%d", &N, &M) == 2);
	intervals.reserve(M+1);
	intervals.resize(M);
	renum.reserve(2*M);
	for(auto &interval : intervals) {
		assert(scanf("%d%d", &interval.first, &interval.second) == 2);
		assert(1 <= interval.first && interval.first < interval.second && interval.second <= N);
		interval.second -= 1;
		renum.push_back(&interval.first);
		renum.push_back(&interval.second);
	}
	
    sort(intervals.begin(), intervals.end());
    int mxr = 1;
    for(auto &interval : intervals) {
        if(mxr+1 < interval.first) {
          printf("0\n");
          return 0;
        }
        mxr = max(mxr, interval.second);
    }
    
	{
		intervals.push_back(pair<int, int>(1, N));
		pair<int, int> &interval = intervals[M];
		interval.second -= 1;
		renum.push_back(&interval.first);
		renum.push_back(&interval.second);
	}

	F = 1;
	renum.push_back(&F);
	N -= 1;
	renum.push_back(&N);

	sort(renum.begin(), renum.end(), [&](const int *a, const int *b){
		return *a < *b;
	});

	for(int i = 0, k = 0; i < renum.size(); ) {
		int j = i, v = *renum[i];
		k += 1;
		for(; j < renum.size() && *renum[j] == v; j++) *renum[j] = k;
		i = j;
	}

	sort(intervals.begin(), intervals.end(), [](const pair<int, int> &a, const pair<int, int> &b) {
		return make_pair(a.first, -a.second) < make_pair(b.first, -b.second);
	});

	// 0. 전처리
	vector<modint> pow2(M+1);
	pow2[0] = 1;
	for(int i = 1; i <= M; i++) {
		pow2[i] = pow2[i-1] * 2;
	}

	// 1. 중복 제거
	vector< pair< pair<int, int>, int> > unique_intervals;
	for(int i = 0; i < intervals.size(); ) {
		int j = i;
		while(j < intervals.size() && intervals[i] == intervals[j])
			j += 1;
		unique_intervals.push_back(make_pair(intervals[i], j - i - (i == 0)));
		i = j;
	}

	// 2.
	stack<int> stk;
	vector< vector<int> > childs(unique_intervals.size());
	vector<int> parent(unique_intervals.size(), -1);
	vector<int> roots;
	modint ans = 1;

	for(int i = 0; i < unique_intervals.size(); i++) {
		pair<int, int> interval; int cnt;
		tie(interval, cnt) = unique_intervals[i];
		while(!stk.empty()) {
			int tp = stk.top();
			if(unique_intervals[tp].first.second < interval.first) {
				stk.pop();
			}else {
				childs[tp].push_back(i);
				parent[i] = tp;
				break;
			}
		}
		if(stk.empty()) {
			roots.push_back(i);
		}
		stk.push(i);
	}

	queue<int> que;
	vector<int> deg(unique_intervals.size());
	vector<modint> ways(unique_intervals.size());
	vector<int> subtree_size(unique_intervals.size());

	for(int i = 0; i < unique_intervals.size(); i++) {
		deg[i] = childs[i].size();
		if(deg[i] == 0) {
			que.push(i);
		}
	}

	while(!que.empty()) {
		int u = que.front(); que.pop();
		pair<int, int> interval; int cnt;
		tie(interval, cnt) = unique_intervals[u];

		subtree_size[u] += cnt;

		int p = parent[u];
		if(p >= 0) {
			if(--deg[p] == 0) que.push(p);
			subtree_size[p] += subtree_size[u];
		}

		pair<int, int> merged(-1, -1);
		for(auto ch : childs[u]) {
			if(merged.first == -1) merged = unique_intervals[ch].first;
			else if(merged.second + 1 == unique_intervals[ch].first.first)
				merged = make_pair(merged.first, unique_intervals[ch].first.second);
			else {
				merged = make_pair(-2, -2);
				break;
			}
		}

		ways[u] = pow2[subtree_size[u] - cnt] * (pow2[cnt] - 1);
		if(merged == interval) {
			modint cur = 1;
			for(int child : childs[u]) cur *= ways[child];
			ways[u] += cur;
		}
	}

	assert(roots.size() == 1);
	for(auto i : roots) {
		ans *= ways[i];
	}
	printf("%d\n", *ans);
	return 0;
}

Compilation message

rail.cpp: In function 'int main()':
rail.cpp:104:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0, k = 0; i < renum.size(); ) {
                          ^
rail.cpp:107:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(; j < renum.size() && *renum[j] == v; j++) *renum[j] = k;
           ^
rail.cpp:124:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0; i < intervals.size(); ) {
                   ^
rail.cpp:126:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   while(j < intervals.size() && intervals[i] == intervals[j])
           ^
rail.cpp:139:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0; i < unique_intervals.size(); i++) {
                   ^
rail.cpp:163:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0; i < unique_intervals.size(); i++) {
                   ^

Subtask #1
0 / 10.0

# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 1944 KB Output is correct
2 Correct 0 ms 1944 KB Output is correct
3 Incorrect 0 ms 1944 KB Output isn't correct
4 Incorrect 0 ms 1944 KB Output isn't correct
5 Correct 0 ms 1944 KB Output is correct
6 Correct 0 ms 1944 KB Output is correct
7 Incorrect 0 ms 1944 KB Output isn't correct
8 Incorrect 0 ms 1944 KB Output isn't correct
9 Correct 0 ms 1944 KB Output is correct
10 Incorrect 0 ms 1944 KB Output isn't correct
11 Correct 0 ms 1944 KB Output is correct
12 Incorrect 0 ms 1944 KB Output isn't correct
13 Correct 0 ms 1944 KB Output is correct
14 Correct 0 ms 1944 KB Output is correct
15 Incorrect 0 ms 1944 KB Output isn't correct
16 Incorrect 0 ms 1944 KB Output isn't correct
17 Correct 0 ms 1944 KB Output is correct
18 Correct 0 ms 1944 KB Output is correct

Subtask #2
0 / 8.0

# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 1944 KB Output is correct
2 Correct 0 ms 1944 KB Output is correct
3 Incorrect 0 ms 1944 KB Output isn't correct
4 Incorrect 0 ms 1944 KB Output isn't correct
5 Correct 0 ms 1944 KB Output is correct
6 Correct 0 ms 1944 KB Output is correct
7 Incorrect 0 ms 1944 KB Output isn't correct
8 Incorrect 0 ms 1944 KB Output isn't correct
9 Correct 0 ms 1944 KB Output is correct
10 Incorrect 0 ms 1944 KB Output isn't correct
11 Correct 0 ms 1944 KB Output is correct
12 Incorrect 0 ms 1944 KB Output isn't correct
13 Correct 0 ms 1944 KB Output is correct
14 Correct 0 ms 1944 KB Output is correct
15 Incorrect 0 ms 1944 KB Output isn't correct
16 Incorrect 0 ms 1944 KB Output isn't correct
17 Correct 0 ms 1944 KB Output is correct
18 Correct 0 ms 1944 KB Output is correct
19 Incorrect 0 ms 1944 KB Output isn't correct
20 Incorrect 0 ms 1944 KB Output isn't correct
21 Correct 0 ms 1944 KB Output is correct
22 Incorrect 0 ms 1944 KB Output isn't correct
23 Incorrect 0 ms 1944 KB Output isn't correct
24 Incorrect 0 ms 1944 KB Output isn't correct
25 Incorrect 0 ms 1944 KB Output isn't correct
26 Incorrect 0 ms 1944 KB Output isn't correct
27 Correct 0 ms 1944 KB Output is correct
28 Correct 0 ms 1944 KB Output is correct
29 Incorrect 0 ms 1944 KB Output isn't correct
30 Incorrect 0 ms 1944 KB Output isn't correct
31 Incorrect 0 ms 1944 KB Output isn't correct
32 Incorrect 0 ms 1944 KB Output isn't correct
33 Correct 0 ms 1944 KB Output is correct
34 Incorrect 0 ms 1944 KB Output isn't correct
35 Correct 0 ms 1944 KB Output is correct

Subtask #3
0 / 25.0

# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 1944 KB Output is correct
2 Correct 0 ms 1944 KB Output is correct
3 Correct 0 ms 1944 KB Output is correct
4 Incorrect 3 ms 2296 KB Output isn't correct
5 Incorrect 119 ms 13732 KB Output isn't correct
6 Incorrect 176 ms 23408 KB Output isn't correct
7 Incorrect 149 ms 23540 KB Output isn't correct
8 Incorrect 0 ms 1944 KB Output isn't correct
9 Incorrect 139 ms 21996 KB Output isn't correct
10 Incorrect 136 ms 22908 KB Output isn't correct
11 Incorrect 56 ms 9136 KB Output isn't correct
12 Incorrect 149 ms 23276 KB Output isn't correct
13 Incorrect 163 ms 23152 KB Output isn't correct
14 Incorrect 69 ms 12888 KB Output isn't correct
15 Correct 139 ms 23276 KB Output is correct
16 Incorrect 66 ms 12888 KB Output isn't correct
17 Incorrect 146 ms 23792 KB Output isn't correct
18 Incorrect 169 ms 23276 KB Output isn't correct
19 Incorrect 176 ms 23788 KB Output isn't correct

Subtask #4
0 / 27.0

# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 1944 KB Output is correct
2 Correct 0 ms 1944 KB Output is correct
3 Incorrect 0 ms 1944 KB Output isn't correct
4 Incorrect 0 ms 1944 KB Output isn't correct
5 Correct 0 ms 1944 KB Output is correct
6 Correct 0 ms 1944 KB Output is correct
7 Incorrect 0 ms 1944 KB Output isn't correct
8 Incorrect 0 ms 1944 KB Output isn't correct
9 Correct 0 ms 1944 KB Output is correct
10 Incorrect 0 ms 1944 KB Output isn't correct
11 Correct 0 ms 1944 KB Output is correct
12 Incorrect 0 ms 1944 KB Output isn't correct
13 Correct 0 ms 1944 KB Output is correct
14 Correct 0 ms 1944 KB Output is correct
15 Incorrect 0 ms 1944 KB Output isn't correct
16 Incorrect 0 ms 1944 KB Output isn't correct
17 Correct 0 ms 1944 KB Output is correct
18 Correct 0 ms 1944 KB Output is correct
19 Incorrect 0 ms 1944 KB Output isn't correct
20 Incorrect 0 ms 1944 KB Output isn't correct
21 Correct 0 ms 1944 KB Output is correct
22 Incorrect 0 ms 1944 KB Output isn't correct
23 Incorrect 0 ms 1944 KB Output isn't correct
24 Incorrect 0 ms 1944 KB Output isn't correct
25 Incorrect 0 ms 1944 KB Output isn't correct
26 Incorrect 0 ms 1944 KB Output isn't correct
27 Correct 0 ms 1944 KB Output is correct
28 Correct 0 ms 1944 KB Output is correct
29 Incorrect 0 ms 1944 KB Output isn't correct
30 Incorrect 0 ms 1944 KB Output isn't correct
31 Incorrect 0 ms 1944 KB Output isn't correct
32 Incorrect 0 ms 1944 KB Output isn't correct
33 Correct 0 ms 1944 KB Output is correct
34 Incorrect 0 ms 1944 KB Output isn't correct
35 Correct 0 ms 1944 KB Output is correct
36 Incorrect 0 ms 2708 KB Output isn't correct
37 Incorrect 3 ms 2544 KB Output isn't correct
38 Incorrect 3 ms 2544 KB Output isn't correct
39 Incorrect 0 ms 2296 KB Output isn't correct
40 Correct 3 ms 2568 KB Output is correct
41 Correct 0 ms 2136 KB Output is correct
42 Incorrect 3 ms 2708 KB Output isn't correct
43 Incorrect 0 ms 1944 KB Output isn't correct
44 Incorrect 3 ms 2700 KB Output isn't correct
45 Correct 0 ms 2296 KB Output is correct
46 Incorrect 0 ms 2708 KB Output isn't correct
47 Incorrect 3 ms 2396 KB Output isn't correct
48 Incorrect 3 ms 2396 KB Output isn't correct
49 Incorrect 0 ms 2296 KB Output isn't correct
50 Incorrect 0 ms 2296 KB Output isn't correct
51 Incorrect 0 ms 2296 KB Output isn't correct
52 Incorrect 0 ms 2076 KB Output isn't correct
53 Correct 0 ms 2136 KB Output is correct
54 Incorrect 0 ms 2244 KB Output isn't correct
55 Correct 0 ms 2136 KB Output is correct

Subtask #5
0 / 30.0

# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 1944 KB Output is correct
2 Correct 0 ms 1944 KB Output is correct
3 Incorrect 0 ms 1944 KB Output isn't correct
4 Incorrect 0 ms 1944 KB Output isn't correct
5 Correct 0 ms 1944 KB Output is correct
6 Correct 0 ms 1944 KB Output is correct
7 Incorrect 0 ms 1944 KB Output isn't correct
8 Incorrect 0 ms 1944 KB Output isn't correct
9 Correct 0 ms 1944 KB Output is correct
10 Incorrect 0 ms 1944 KB Output isn't correct
11 Correct 0 ms 1944 KB Output is correct
12 Incorrect 0 ms 1944 KB Output isn't correct
13 Correct 0 ms 1944 KB Output is correct
14 Correct 0 ms 1944 KB Output is correct
15 Incorrect 0 ms 1944 KB Output isn't correct
16 Incorrect 0 ms 1944 KB Output isn't correct
17 Correct 0 ms 1944 KB Output is correct
18 Correct 0 ms 1944 KB Output is correct
19 Incorrect 0 ms 1944 KB Output isn't correct
20 Incorrect 0 ms 1944 KB Output isn't correct
21 Correct 0 ms 1944 KB Output is correct
22 Incorrect 0 ms 1944 KB Output isn't correct
23 Incorrect 0 ms 1944 KB Output isn't correct
24 Incorrect 0 ms 1944 KB Output isn't correct
25 Incorrect 0 ms 1944 KB Output isn't correct
26 Incorrect 0 ms 1944 KB Output isn't correct
27 Correct 0 ms 1944 KB Output is correct
28 Correct 0 ms 1944 KB Output is correct
29 Incorrect 0 ms 1944 KB Output isn't correct
30 Incorrect 0 ms 1944 KB Output isn't correct
31 Incorrect 0 ms 1944 KB Output isn't correct
32 Incorrect 0 ms 1944 KB Output isn't correct
33 Correct 0 ms 1944 KB Output is correct
34 Incorrect 0 ms 1944 KB Output isn't correct
35 Correct 0 ms 1944 KB Output is correct
36 Correct 0 ms 1944 KB Output is correct
37 Correct 0 ms 1944 KB Output is correct
38 Correct 0 ms 1944 KB Output is correct
39 Incorrect 3 ms 2296 KB Output isn't correct
40 Incorrect 119 ms 13732 KB Output isn't correct
41 Incorrect 176 ms 23408 KB Output isn't correct
42 Incorrect 149 ms 23540 KB Output isn't correct
43 Incorrect 0 ms 1944 KB Output isn't correct
44 Incorrect 139 ms 21996 KB Output isn't correct
45 Incorrect 136 ms 22908 KB Output isn't correct
46 Incorrect 56 ms 9136 KB Output isn't correct
47 Incorrect 149 ms 23276 KB Output isn't correct
48 Incorrect 163 ms 23152 KB Output isn't correct
49 Incorrect 69 ms 12888 KB Output isn't correct
50 Correct 139 ms 23276 KB Output is correct
51 Incorrect 66 ms 12888 KB Output isn't correct
52 Incorrect 146 ms 23792 KB Output isn't correct
53 Incorrect 169 ms 23276 KB Output isn't correct
54 Incorrect 176 ms 23788 KB Output isn't correct
55 Incorrect 0 ms 2708 KB Output isn't correct
56 Incorrect 3 ms 2544 KB Output isn't correct
57 Incorrect 3 ms 2544 KB Output isn't correct
58 Incorrect 0 ms 2296 KB Output isn't correct
59 Correct 3 ms 2568 KB Output is correct
60 Correct 0 ms 2136 KB Output is correct
61 Incorrect 3 ms 2708 KB Output isn't correct
62 Incorrect 0 ms 1944 KB Output isn't correct
63 Incorrect 3 ms 2700 KB Output isn't correct
64 Correct 0 ms 2296 KB Output is correct
65 Incorrect 0 ms 2708 KB Output isn't correct
66 Incorrect 3 ms 2396 KB Output isn't correct
67 Incorrect 3 ms 2396 KB Output isn't correct
68 Incorrect 0 ms 2296 KB Output isn't correct
69 Incorrect 0 ms 2296 KB Output isn't correct
70 Incorrect 0 ms 2296 KB Output isn't correct
71 Incorrect 0 ms 2076 KB Output isn't correct
72 Correct 0 ms 2136 KB Output is correct
73 Incorrect 0 ms 2244 KB Output isn't correct
74 Correct 0 ms 2136 KB Output is correct
75 Incorrect 189 ms 28580 KB Output isn't correct
76 Incorrect 136 ms 20500 KB Output isn't correct
77 Incorrect 129 ms 27220 KB Output isn't correct
78 Incorrect 63 ms 12888 KB Output isn't correct
79 Correct 83 ms 6612 KB Output is correct
80 Incorrect 169 ms 28580 KB Output isn't correct
81 Incorrect 3 ms 2708 KB Output isn't correct
82 Incorrect 176 ms 27800 KB Output isn't correct
83 Correct 66 ms 12888 KB Output is correct
84 Incorrect 176 ms 28580 KB Output isn't correct
85 Incorrect 166 ms 19592 KB Output isn't correct
86 Incorrect 176 ms 19600 KB Output isn't correct
87 Incorrect 89 ms 12888 KB Output isn't correct
88 Incorrect 89 ms 12888 KB Output isn't correct
89 Incorrect 189 ms 28580 KB Output isn't correct
90 Incorrect 186 ms 28580 KB Output isn't correct
91 Incorrect 189 ms 28580 KB Output isn't correct
92 Correct 83 ms 6548 KB Output is correct
93 Incorrect 179 ms 19588 KB Output isn't correct
94 Incorrect 173 ms 28580 KB Output isn't correct
95 Incorrect 179 ms 28580 KB Output isn't correct