oj.uz

Submission #386797

# Submission time Handle Problem Language Result Execution time Memory
386797 2021-04-07T10:25:53 Z maximath_1 Alternating Current (BOI18_alternating) C++11
19 / 100
 84 ms 7660 KB 
#include <iostream>
#include <string>
#include <math.h>
#include <algorithm>
#include <vector>
#include <string.h>
#include <numeric>
#include <iostream>
#include <queue>
#include <assert.h>
#include <map>
#include <set>
#include <limits.h>
#include <random>
#include <chrono>
using namespace std;
 
#define ll long long
#define ld long double
const int MX = 5005;
const int BLOCK = 105;
const ll inf = 8000000000000000069ll;
const ll mod = 1e9 + 7;
const ll inv2 = (mod + 1) / 2;
const int dxh[] = {1, 1, -1, -1, 2, 2, -2, -2};
const int dyh[] = {2, -2, 2, -2, 1, -1, 1, -1}; // horse
const int dx[] = {1, -1, 0, 0, 0, 0};
const int dy[] = {0, 0, 1, -1, 0, 0}; // adj
const int dz[] = {0, 0, 0, 0, 1, -1};
const int dxd[] = {1, 1, 1, 0, -1, -1, -1, 0};
const int dyd[] = {1, 0, -1, -1, -1, 0, 1, 1}; // diag

mt19937 rng(time(NULL));

int n, m;
vector<pair<pair<int, int>, int> > v;

void imp(){
	cout << "impossible\n";
	exit(0);
}

void solve(){
	set<pair<int, int> > s;
	vector<int> ans(m + 1, 0);

	int c1 = 0, c2 = 0;
	for(int j = 0, i = 1; i <= n; i ++){
		for(; j < m && v[j].first.first == i; j ++)
			s.insert(make_pair(v[j].first.second, v[j].second));
		for(; s.size() && s.begin() -> first < i;)
			s.erase(s.begin());

		if(c1 < i){
			if(s.empty()) imp();
			c1 = s.begin() -> first;
			ans[s.begin() -> second] = 1;
			s.erase(s.begin());
		}

		if(c2 < i){
			if(s.empty()) imp();
			c2 = s.begin() -> first;
			ans[s.begin() -> second] = 0;
			s.erase(s.begin());
		}
	}

	for(int i = 0; i < m; i ++)
		cout << ans[i];
	exit(0);
}

int main(){
	cin.tie(0) -> sync_with_stdio(0);
	cin >> n >> m;
	v.resize(m);

	bool aa = 1;
	for(int i = 0; i < m; i ++){
		cin >> v[i].first.first >> v[i].first.second;
		if(v[i].first.first > v[i].first.second) aa = 0;
		v[i].second = i;
	}

	sort(v.begin(), v.end());

	if(aa) solve();
}

Subtask #1
0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 364 KB Output is correct
2 Correct 1 ms 364 KB Output is correct
3 Incorrect 1 ms 364 KB Unexpected end of file - token expected
4 Halted 0 ms 0 KB -

Subtask #2
0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 364 KB Output is correct
2 Correct 1 ms 364 KB Output is correct
3 Incorrect 1 ms 364 KB Unexpected end of file - token expected
4 Halted 0 ms 0 KB -

Subtask #3
0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 364 KB Output is correct
2 Correct 1 ms 364 KB Output is correct
3 Incorrect 1 ms 364 KB Unexpected end of file - token expected
4 Halted 0 ms 0 KB -

Subtask #4
19.0 / 19.0

# Verdict Execution time Memory Grader output
1 Correct 45 ms 7660 KB Output is correct
2 Correct 1 ms 384 KB Output is correct
3 Correct 12 ms 1644 KB Output is correct
4 Correct 25 ms 4076 KB Output is correct
5 Correct 37 ms 3072 KB Output is correct
6 Correct 32 ms 3052 KB Output is correct
7 Correct 36 ms 2924 KB Output is correct
8 Correct 3 ms 364 KB Output is correct
9 Correct 2 ms 364 KB Output is correct
10 Correct 40 ms 3180 KB Output is correct
11 Correct 30 ms 2412 KB Output is correct
12 Correct 34 ms 2924 KB Output is correct
13 Correct 2 ms 364 KB Output is correct
14 Correct 1 ms 364 KB Output is correct
15 Correct 42 ms 3180 KB Output is correct
16 Correct 30 ms 4076 KB Output is correct
17 Correct 84 ms 5484 KB Output is correct
18 Correct 71 ms 5484 KB Output is correct
19 Correct 3 ms 492 KB Output is correct
20 Correct 39 ms 3112 KB Output is correct

Subtask #5
0 / 26.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 364 KB Output is correct
2 Correct 1 ms 364 KB Output is correct
3 Incorrect 1 ms 364 KB Unexpected end of file - token expected
4 Halted 0 ms 0 KB -