oj.uz

Submission #703951

# Submission time Handle Problem Language Result Execution time Memory
703951 2023-03-01T05:52:23 Z vjudge1 Event Hopping (BOI22_events) C++17
10 / 100
 1500 ms 32876 KB 
#include <bits/stdc++.h>                     
  
#define ll long long 
#define pb push_back
#define all(v) v.begin(),v.end()
#define rall(v) v.rbegin(),v.rend()
#define sz(v) (int)v.size()
#define x first
#define y second
#define nl "\n"
  
using namespace std;
  
const int N = (int)1e5 + 7;
const int M = (int)2e6 + 5e5 + 7;
const ll MOD = (ll)1e9;                    
const int inf = (int)1e9 + 7;
const int B = (int)390;
const ll INF = (ll)1e18 + 7;
  
pair<int, int> dir[] = {{-1, 0}, {1, 0}, {0, 1}, {0, -1}};
 
bool bit(int mask, int i) {
    return (mask >> i & 1);
}
  
int sum(int x, int y) {
    x += y;
    if(x >= MOD) x -= MOD;
    return x;
}
  
int mult(int x, int y) {
    return 1ll * x * y % MOD;
}

int n, q;
int l[N], r[N], d[N];
vector<int> g[N];

void solve() {	
	cin >> n >> q;
	for(int i = 1; i <= n; ++i) {
		cin >> l[i] >> r[i];
	}
	for(int i = 1; i <= n; ++i) {
		for(int j = 1; j <= n; ++j) {
			if(l[j] <= r[i] && r[i] <= r[j]) {
				g[i].pb(j);
			}
		}
	}

	while(q--) {
		int s, t;
		cin >> s >> t;
		queue<int> q;
		fill(d + 1, d + 1 + n, inf);
		d[s] = 0;
		q.push(s);
		while(!q.empty()) {
			int v = q.front();
			q.pop();
			for(auto to : g[v]) {
				if(d[v] + 1 < d[to]) {
					d[to] = d[v] + 1;
					q.push(to);
				}
			}
		}
		if(d[t] == inf) cout << "impossible\n";
		else cout << d[t] << nl;			
	}
}       
 
  
signed main() {                   
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    int test = 1;                       
    //cin >> test;
    for(int i = 1; i <= test; ++i) {
        //cout << "Case " << i << ":\n";
        solve();
    }
    return 0;
}                   
/*
possible causes of error :
* array  bounds
* int overflow
* special case (n == 1?)
* haven't clean something
* wrong N | M | inf | INF | MOD

* try to write brute force to find test
* don't waste time
* don't write bullshit
* solution is easy
*/

Subtask #1
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 2644 KB Output is correct
2 Execution timed out 1560 ms 5660 KB Time limit exceeded
3 Halted 0 ms 0 KB -

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2644 KB Output is correct
2 Correct 2 ms 2676 KB Output is correct
3 Correct 8 ms 2644 KB Output is correct
4 Correct 6 ms 2724 KB Output is correct
5 Correct 7 ms 2676 KB Output is correct
6 Correct 11 ms 3412 KB Output is correct
7 Correct 18 ms 4308 KB Output is correct
8 Correct 19 ms 5376 KB Output is correct
9 Correct 76 ms 6612 KB Output is correct

Subtask #3
0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2644 KB Output is correct
2 Correct 2 ms 2676 KB Output is correct
3 Correct 8 ms 2644 KB Output is correct
4 Correct 6 ms 2724 KB Output is correct
5 Correct 7 ms 2676 KB Output is correct
6 Correct 11 ms 3412 KB Output is correct
7 Correct 18 ms 4308 KB Output is correct
8 Correct 19 ms 5376 KB Output is correct
9 Correct 76 ms 6612 KB Output is correct
10 Correct 2 ms 2644 KB Output is correct
11 Correct 2 ms 2676 KB Output is correct
12 Correct 9 ms 2644 KB Output is correct
13 Correct 7 ms 2684 KB Output is correct
14 Correct 7 ms 2684 KB Output is correct
15 Correct 12 ms 3424 KB Output is correct
16 Correct 18 ms 4244 KB Output is correct
17 Correct 20 ms 5332 KB Output is correct
18 Correct 81 ms 6724 KB Output is correct
19 Execution timed out 1591 ms 32876 KB Time limit exceeded
20 Halted 0 ms 0 KB -

Subtask #4
0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2644 KB Output is correct
2 Correct 2 ms 2676 KB Output is correct
3 Correct 8 ms 2644 KB Output is correct
4 Correct 6 ms 2724 KB Output is correct
5 Correct 7 ms 2676 KB Output is correct
6 Correct 11 ms 3412 KB Output is correct
7 Correct 18 ms 4308 KB Output is correct
8 Correct 19 ms 5376 KB Output is correct
9 Correct 76 ms 6612 KB Output is correct
10 Correct 2 ms 2644 KB Output is correct
11 Correct 2 ms 2644 KB Output is correct
12 Correct 8 ms 2644 KB Output is correct
13 Correct 7 ms 2684 KB Output is correct
14 Correct 7 ms 2684 KB Output is correct
15 Correct 10 ms 3496 KB Output is correct
16 Correct 19 ms 4320 KB Output is correct
17 Correct 20 ms 5400 KB Output is correct
18 Correct 89 ms 6656 KB Output is correct
19 Execution timed out 1570 ms 5484 KB Time limit exceeded
20 Halted 0 ms 0 KB -

Subtask #5
0 / 20.0

# Verdict Execution time Memory Grader output
1 Execution timed out 1541 ms 5616 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #6
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 2644 KB Output is correct
2 Execution timed out 1560 ms 5660 KB Time limit exceeded
3 Halted 0 ms 0 KB -