oj.uz

Submission #106162

# Submission time Handle Problem Language Result Execution time Memory
106162 2019-04-17T00:10:17 Z Noam527 Alternating Current (BOI18_alternating) C++17
32 / 100
 121 ms 15448 KB 
#include <bits/stdc++.h>
#define CHECK cout << "ok" << endl
#define finish(x) return cout << x << endl, 0
typedef long long ll;
typedef long double ldb;
const int md = 1e9 + 7;
const ll inf = 1e18;
const int OO = 0;
const int OOO = 1;
using namespace std;

struct edge {
	int to, i;
	edge(int tt = 0, int ii = 0) : to(tt), i(ii) {}
};

int n, m;
int C[100005] = {};
int dp[200005], to[200005];
int range[200005] = {};

vector<edge> g[200005];
vector<int> vis; int nxtcol = 5;
vector<int> path;

string ans;

void add(int l, int r) {
	C[l]++;
	C[r + 1]--;
}
void pre() {
	for (int i = 1; i <= n; i++) C[i] += C[i - 1];
	for (int i = 1; i <= n; i++) {
		if (C[i] == 1) {
			cout << "impossible\n";
			exit(0);
		}
		C[i] = max(0, min(1, C[i] - 2));
		if (C[i]) {
			if (OO) {
				cout << "from C adding " << i << " " << i - 1 << '\n';
			}
			g[i].push_back(edge(i - 1, -1));
			g[i + n].push_back(edge(i - 1 + n, -1));
		}
	}
}

bool dfs(int v, int tar) {
	if (OO) {
		cout << "dfsing " << v << " tar " << tar << '\n';
	}
	if (v == tar) return true;
	if (vis[v % n] == nxtcol) return false;
	vis[v % n] = nxtcol;
	for (const auto &i : g[v]) {
		path.push_back(i.i);
		if (dfs(i.to, tar)) return true;
		path.pop_back();
	}
	return false;
}

bool check(int v) {
	if (OO) {
		cout << "starting check on " << v << '\n';
	}
	nxtcol++;
	for (const auto &i : g[v]) {
		if (i.to != v - 1) {
			path.push_back(i.i);
			if (dfs(i.to, v + n)) return true;
			path.pop_back();
		}
	}
	return false;
}

int main() {
	ios::sync_with_stdio(0), cin.tie(0);
	cin >> n >> m;
	for (int i = 0, l, r; i < m; i++) {
		cin >> l >> r;
		if (l > r) {
			add(l, n);
			add(1, r);
			l--;
			r += n;
			if (OO) cout << "from input adding " << l << " " << r << '\n';
			g[l].push_back(edge(r, i));
			g[l + n].push_back(edge(2 * n, i));
		}
		else {
			add(l, r);
			l--;
			if (OO) cout << "from input adding " << l << " " << r << '\n';
			g[l].push_back(edge(r, i));
			g[l + n].push_back(edge(r + n, i));
		}
	}
	pre();

	ans.resize(m, '1');
	vis.resize(n, 0);
	if (*min_element(C + 1, C + n + 1) > 0) {
		for (int i = 0; i < n; i++) {
			if (check(i)) {
				for (const auto &j : path)
					if (j != -1) ans[j] = '0';
				finish(ans);
			}
		}
		return 0;
	}
	int ind = 1;
	while (C[ind] > 0) ind++;
	for (int i = ind - 1; i >= 0; i--) {
		for (const auto &j : g[i])
			if (ind <= j.to) {
				if (!check(i)) finish("impossible");
				for (const auto &j : path)
					if (j != -1) ans[j] = '0';
				finish(ans);
			}
	}
	for (int i = n - 1; i >= ind; i--) {
		for (const auto &j : g[i])
			if (ind + n <= j.to) {
				if (!check(i)) finish("impossible");
				for (const auto &j : path)
					if (j != -1) ans[j] = '0';
				finish(ans);
			}
	}
}

Subtask #1
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 4992 KB Output is correct
2 Correct 6 ms 5092 KB Output is correct
3 Correct 7 ms 4992 KB Output is correct
4 Correct 6 ms 5120 KB Output is correct
5 Correct 6 ms 4992 KB Output is correct
6 Correct 6 ms 5100 KB Output is correct
7 Correct 6 ms 5120 KB Output is correct
8 Correct 7 ms 5120 KB Output is correct
9 Correct 7 ms 4992 KB Output is correct
10 Correct 8 ms 4992 KB Output is correct
11 Correct 7 ms 4992 KB Output is correct
12 Correct 6 ms 4992 KB Output is correct
13 Correct 6 ms 4992 KB Output is correct
14 Correct 8 ms 5120 KB Output is correct
15 Correct 5 ms 4992 KB Output is correct
16 Correct 7 ms 4992 KB Output is correct
17 Correct 5 ms 4988 KB Output is correct
18 Correct 7 ms 4992 KB Output is correct
19 Correct 6 ms 5120 KB Output is correct
20 Correct 7 ms 4992 KB Output is correct
21 Correct 7 ms 4992 KB Output is correct
22 Correct 7 ms 4992 KB Output is correct
23 Correct 6 ms 5120 KB Output is correct
24 Correct 6 ms 4992 KB Output is correct
25 Correct 7 ms 5120 KB Output is correct
26 Correct 7 ms 4992 KB Output is correct
27 Correct 6 ms 4992 KB Output is correct
28 Correct 7 ms 4992 KB Output is correct
29 Correct 6 ms 4992 KB Output is correct
30 Correct 6 ms 4992 KB Output is correct
31 Correct 6 ms 4992 KB Output is correct
32 Correct 7 ms 4992 KB Output is correct
33 Correct 7 ms 4992 KB Output is correct
34 Correct 7 ms 4992 KB Output is correct
35 Correct 5 ms 4988 KB Output is correct
36 Correct 6 ms 5120 KB Output is correct
37 Correct 7 ms 4992 KB Output is correct
38 Correct 6 ms 4992 KB Output is correct
39 Correct 6 ms 4992 KB Output is correct
40 Correct 7 ms 5164 KB Output is correct

Subtask #2
0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 4992 KB Output is correct
2 Correct 6 ms 5092 KB Output is correct
3 Correct 7 ms 4992 KB Output is correct
4 Correct 6 ms 5120 KB Output is correct
5 Correct 6 ms 4992 KB Output is correct
6 Correct 6 ms 5100 KB Output is correct
7 Correct 6 ms 5120 KB Output is correct
8 Correct 7 ms 5120 KB Output is correct
9 Correct 7 ms 4992 KB Output is correct
10 Correct 8 ms 4992 KB Output is correct
11 Correct 7 ms 4992 KB Output is correct
12 Correct 6 ms 4992 KB Output is correct
13 Correct 6 ms 4992 KB Output is correct
14 Correct 8 ms 5120 KB Output is correct
15 Correct 5 ms 4992 KB Output is correct
16 Correct 7 ms 4992 KB Output is correct
17 Correct 5 ms 4988 KB Output is correct
18 Correct 7 ms 4992 KB Output is correct
19 Correct 6 ms 5120 KB Output is correct
20 Correct 7 ms 4992 KB Output is correct
21 Correct 7 ms 4992 KB Output is correct
22 Correct 7 ms 4992 KB Output is correct
23 Correct 6 ms 5120 KB Output is correct
24 Correct 6 ms 4992 KB Output is correct
25 Correct 7 ms 5120 KB Output is correct
26 Correct 7 ms 4992 KB Output is correct
27 Correct 6 ms 4992 KB Output is correct
28 Correct 7 ms 4992 KB Output is correct
29 Correct 6 ms 4992 KB Output is correct
30 Correct 6 ms 4992 KB Output is correct
31 Correct 6 ms 4992 KB Output is correct
32 Correct 7 ms 4992 KB Output is correct
33 Correct 7 ms 4992 KB Output is correct
34 Correct 7 ms 4992 KB Output is correct
35 Correct 5 ms 4988 KB Output is correct
36 Correct 6 ms 5120 KB Output is correct
37 Correct 7 ms 4992 KB Output is correct
38 Correct 6 ms 4992 KB Output is correct
39 Correct 6 ms 4992 KB Output is correct
40 Correct 7 ms 5164 KB Output is correct
41 Correct 7 ms 5120 KB Output is correct
42 Correct 7 ms 5120 KB Output is correct
43 Correct 7 ms 4992 KB Output is correct
44 Incorrect 7 ms 5120 KB no wires in direction 1 between segments 4 and 22
45 Halted 0 ms 0 KB -

Subtask #3
0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 4992 KB Output is correct
2 Correct 6 ms 5092 KB Output is correct
3 Correct 7 ms 4992 KB Output is correct
4 Correct 6 ms 5120 KB Output is correct
5 Correct 6 ms 4992 KB Output is correct
6 Correct 6 ms 5100 KB Output is correct
7 Correct 6 ms 5120 KB Output is correct
8 Correct 7 ms 5120 KB Output is correct
9 Correct 7 ms 4992 KB Output is correct
10 Correct 8 ms 4992 KB Output is correct
11 Correct 7 ms 4992 KB Output is correct
12 Correct 6 ms 4992 KB Output is correct
13 Correct 6 ms 4992 KB Output is correct
14 Correct 8 ms 5120 KB Output is correct
15 Correct 5 ms 4992 KB Output is correct
16 Correct 7 ms 4992 KB Output is correct
17 Correct 5 ms 4988 KB Output is correct
18 Correct 7 ms 4992 KB Output is correct
19 Correct 6 ms 5120 KB Output is correct
20 Correct 7 ms 4992 KB Output is correct
21 Correct 7 ms 4992 KB Output is correct
22 Correct 7 ms 4992 KB Output is correct
23 Correct 6 ms 5120 KB Output is correct
24 Correct 6 ms 4992 KB Output is correct
25 Correct 7 ms 5120 KB Output is correct
26 Correct 7 ms 4992 KB Output is correct
27 Correct 6 ms 4992 KB Output is correct
28 Correct 7 ms 4992 KB Output is correct
29 Correct 6 ms 4992 KB Output is correct
30 Correct 6 ms 4992 KB Output is correct
31 Correct 6 ms 4992 KB Output is correct
32 Correct 7 ms 4992 KB Output is correct
33 Correct 7 ms 4992 KB Output is correct
34 Correct 7 ms 4992 KB Output is correct
35 Correct 5 ms 4988 KB Output is correct
36 Correct 6 ms 5120 KB Output is correct
37 Correct 7 ms 4992 KB Output is correct
38 Correct 6 ms 4992 KB Output is correct
39 Correct 6 ms 4992 KB Output is correct
40 Correct 7 ms 5164 KB Output is correct
41 Correct 7 ms 5120 KB Output is correct
42 Correct 7 ms 5120 KB Output is correct
43 Correct 7 ms 4992 KB Output is correct
44 Incorrect 7 ms 5120 KB no wires in direction 1 between segments 4 and 22
45 Halted 0 ms 0 KB -

Subtask #4
19.0 / 19.0

# Verdict Execution time Memory Grader output
1 Correct 37 ms 13796 KB Output is correct
2 Correct 8 ms 5860 KB Output is correct
3 Correct 26 ms 8652 KB Output is correct
4 Correct 42 ms 12212 KB Output is correct
5 Correct 87 ms 12404 KB Output is correct
6 Correct 100 ms 10544 KB Output is correct
7 Correct 92 ms 12788 KB Output is correct
8 Correct 15 ms 8576 KB Output is correct
9 Correct 16 ms 8576 KB Output is correct
10 Correct 105 ms 12660 KB Output is correct
11 Correct 73 ms 11508 KB Output is correct
12 Correct 95 ms 11640 KB Output is correct
13 Correct 9 ms 5760 KB Output is correct
14 Correct 7 ms 5760 KB Output is correct
15 Correct 121 ms 15000 KB Output is correct
16 Correct 32 ms 11740 KB Output is correct
17 Correct 111 ms 15448 KB Output is correct
18 Correct 35 ms 7928 KB Output is correct
19 Correct 8 ms 5760 KB Output is correct
20 Correct 37 ms 10612 KB Output is correct

Subtask #5
0 / 26.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 4992 KB Output is correct
2 Correct 6 ms 5092 KB Output is correct
3 Correct 7 ms 4992 KB Output is correct
4 Correct 6 ms 5120 KB Output is correct
5 Correct 6 ms 4992 KB Output is correct
6 Correct 6 ms 5100 KB Output is correct
7 Correct 6 ms 5120 KB Output is correct
8 Correct 7 ms 5120 KB Output is correct
9 Correct 7 ms 4992 KB Output is correct
10 Correct 8 ms 4992 KB Output is correct
11 Correct 7 ms 4992 KB Output is correct
12 Correct 6 ms 4992 KB Output is correct
13 Correct 6 ms 4992 KB Output is correct
14 Correct 8 ms 5120 KB Output is correct
15 Correct 5 ms 4992 KB Output is correct
16 Correct 7 ms 4992 KB Output is correct
17 Correct 5 ms 4988 KB Output is correct
18 Correct 7 ms 4992 KB Output is correct
19 Correct 6 ms 5120 KB Output is correct
20 Correct 7 ms 4992 KB Output is correct
21 Correct 7 ms 4992 KB Output is correct
22 Correct 7 ms 4992 KB Output is correct
23 Correct 6 ms 5120 KB Output is correct
24 Correct 6 ms 4992 KB Output is correct
25 Correct 7 ms 5120 KB Output is correct
26 Correct 7 ms 4992 KB Output is correct
27 Correct 6 ms 4992 KB Output is correct
28 Correct 7 ms 4992 KB Output is correct
29 Correct 6 ms 4992 KB Output is correct
30 Correct 6 ms 4992 KB Output is correct
31 Correct 6 ms 4992 KB Output is correct
32 Correct 7 ms 4992 KB Output is correct
33 Correct 7 ms 4992 KB Output is correct
34 Correct 7 ms 4992 KB Output is correct
35 Correct 5 ms 4988 KB Output is correct
36 Correct 6 ms 5120 KB Output is correct
37 Correct 7 ms 4992 KB Output is correct
38 Correct 6 ms 4992 KB Output is correct
39 Correct 6 ms 4992 KB Output is correct
40 Correct 7 ms 5164 KB Output is correct
41 Correct 7 ms 5120 KB Output is correct
42 Correct 7 ms 5120 KB Output is correct
43 Correct 7 ms 4992 KB Output is correct
44 Incorrect 7 ms 5120 KB no wires in direction 1 between segments 4 and 22
45 Halted 0 ms 0 KB -