#include <bits/stdc++.h>
using namespace std;
using pii = pair<int, int>;
const int N = 3e4 + 5;
const int oo = 1e9;
const int SQRT = 175;
#define eb emplace_back
struct node {
int w, u, s;
node() {
w = u = s = 0;
}
node(int w, int u, int s) : w(w), u(u), s(s) {}
friend bool operator > (node a, node b) {
return a.w > b.w;
}
};
int n, m;
int dist[N][SQRT];
pii a[N];
vector<int> adj[N];
priority_queue<node, vector<node>, greater<node>> Q;
bool vis[N];
void update(int u, int v, int w, int cur) {
if(dist[v][cur] > dist[u][cur] + w) {
dist[v][cur] = dist[u][cur] + w;
Q.emplace(dist[v][cur], v, cur);
}
}
int main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
cin >> n >> m;
for(int i = 0; i < m; i++) {
int u, v;
cin >> u >> v;
adj[u].eb(v);
a[i] = {u, v};
}
memset(dist, 0x3f, sizeof dist);
dist[a[0].first][0] = 0;
Q.emplace(0, a[0].first, 0);
while(!Q.empty()) {
node top = Q.top();
Q.pop();
int u = top.u;
int cur = top.s;
if(dist[u][cur] != top.w)
continue;
if(u == a[1].first)
return cout << dist[a[1].first][cur], 0;
if(cur) {
if(u + cur <= n)
update(u, u + cur, 1, cur);
if(u - cur >= 0)
update(u, u - cur, 1, cur);
}
for(int v : adj[u]) {
if(dist[u][v] > dist[u][cur])
dist[u][v] = dist[u][cur];
if(u + v <= n)
update(u, u + v, 1, v);
if(u - v >= 0)
update(u, u - v, 1, v);
}
}
cout << -1;
}
/*
5 3
0 2
1 1
4 1
*/
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
4 ms |
21852 KB |
Output is correct |
2 |
Correct |
3 ms |
21852 KB |
Output is correct |
3 |
Correct |
3 ms |
21852 KB |
Output is correct |
4 |
Correct |
3 ms |
21852 KB |
Output is correct |
5 |
Correct |
3 ms |
21852 KB |
Output is correct |
6 |
Correct |
3 ms |
21852 KB |
Output is correct |
7 |
Correct |
3 ms |
21908 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
3 ms |
21852 KB |
Output is correct |
2 |
Correct |
3 ms |
21848 KB |
Output is correct |
3 |
Correct |
4 ms |
21852 KB |
Output is correct |
4 |
Correct |
3 ms |
21852 KB |
Output is correct |
5 |
Correct |
3 ms |
21852 KB |
Output is correct |
6 |
Correct |
4 ms |
21852 KB |
Output is correct |
7 |
Correct |
3 ms |
21852 KB |
Output is correct |
8 |
Correct |
3 ms |
21852 KB |
Output is correct |
9 |
Correct |
3 ms |
21852 KB |
Output is correct |
10 |
Correct |
3 ms |
21848 KB |
Output is correct |
11 |
Correct |
3 ms |
21852 KB |
Output is correct |
12 |
Correct |
3 ms |
21852 KB |
Output is correct |
13 |
Correct |
4 ms |
21848 KB |
Output is correct |
14 |
Correct |
4 ms |
22004 KB |
Output is correct |
15 |
Correct |
3 ms |
21852 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
3 ms |
21852 KB |
Output is correct |
2 |
Correct |
3 ms |
21852 KB |
Output is correct |
3 |
Correct |
4 ms |
21852 KB |
Output is correct |
4 |
Correct |
4 ms |
21852 KB |
Output is correct |
5 |
Correct |
3 ms |
21852 KB |
Output is correct |
6 |
Correct |
3 ms |
21852 KB |
Output is correct |
7 |
Correct |
4 ms |
21852 KB |
Output is correct |
8 |
Correct |
3 ms |
21852 KB |
Output is correct |
9 |
Correct |
3 ms |
21848 KB |
Output is correct |
10 |
Correct |
4 ms |
21852 KB |
Output is correct |
11 |
Correct |
3 ms |
21852 KB |
Output is correct |
12 |
Correct |
3 ms |
21852 KB |
Output is correct |
13 |
Correct |
3 ms |
21920 KB |
Output is correct |
14 |
Correct |
4 ms |
21852 KB |
Output is correct |
15 |
Correct |
4 ms |
21852 KB |
Output is correct |
16 |
Correct |
3 ms |
21888 KB |
Output is correct |
17 |
Correct |
3 ms |
21852 KB |
Output is correct |
18 |
Correct |
3 ms |
21852 KB |
Output is correct |
19 |
Correct |
3 ms |
21852 KB |
Output is correct |
20 |
Correct |
3 ms |
21852 KB |
Output is correct |
21 |
Correct |
3 ms |
21852 KB |
Output is correct |
22 |
Correct |
3 ms |
21848 KB |
Output is correct |
23 |
Correct |
4 ms |
21852 KB |
Output is correct |
24 |
Correct |
4 ms |
21852 KB |
Output is correct |
25 |
Correct |
4 ms |
21852 KB |
Output is correct |
26 |
Correct |
3 ms |
21852 KB |
Output is correct |
27 |
Correct |
3 ms |
21836 KB |
Output is correct |
28 |
Incorrect |
3 ms |
21852 KB |
Output isn't correct |
29 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
3 ms |
21852 KB |
Output is correct |
2 |
Correct |
3 ms |
21852 KB |
Output is correct |
3 |
Correct |
3 ms |
21852 KB |
Output is correct |
4 |
Correct |
3 ms |
21848 KB |
Output is correct |
5 |
Correct |
3 ms |
21852 KB |
Output is correct |
6 |
Correct |
3 ms |
21836 KB |
Output is correct |
7 |
Correct |
3 ms |
21852 KB |
Output is correct |
8 |
Correct |
3 ms |
21852 KB |
Output is correct |
9 |
Correct |
3 ms |
21848 KB |
Output is correct |
10 |
Correct |
3 ms |
21852 KB |
Output is correct |
11 |
Correct |
3 ms |
21852 KB |
Output is correct |
12 |
Correct |
3 ms |
21852 KB |
Output is correct |
13 |
Correct |
4 ms |
21852 KB |
Output is correct |
14 |
Correct |
4 ms |
21852 KB |
Output is correct |
15 |
Correct |
4 ms |
21852 KB |
Output is correct |
16 |
Correct |
3 ms |
21852 KB |
Output is correct |
17 |
Correct |
4 ms |
21848 KB |
Output is correct |
18 |
Correct |
3 ms |
21852 KB |
Output is correct |
19 |
Correct |
3 ms |
21916 KB |
Output is correct |
20 |
Correct |
4 ms |
21852 KB |
Output is correct |
21 |
Correct |
3 ms |
21852 KB |
Output is correct |
22 |
Correct |
3 ms |
21852 KB |
Output is correct |
23 |
Correct |
4 ms |
21852 KB |
Output is correct |
24 |
Correct |
4 ms |
21852 KB |
Output is correct |
25 |
Correct |
4 ms |
21852 KB |
Output is correct |
26 |
Correct |
3 ms |
21852 KB |
Output is correct |
27 |
Correct |
3 ms |
21852 KB |
Output is correct |
28 |
Incorrect |
3 ms |
21852 KB |
Output isn't correct |
29 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
3 ms |
21852 KB |
Output is correct |
2 |
Correct |
4 ms |
21888 KB |
Output is correct |
3 |
Correct |
3 ms |
21852 KB |
Output is correct |
4 |
Correct |
3 ms |
21852 KB |
Output is correct |
5 |
Correct |
3 ms |
21852 KB |
Output is correct |
6 |
Correct |
3 ms |
21852 KB |
Output is correct |
7 |
Correct |
3 ms |
21852 KB |
Output is correct |
8 |
Correct |
3 ms |
21852 KB |
Output is correct |
9 |
Correct |
3 ms |
21852 KB |
Output is correct |
10 |
Correct |
3 ms |
21852 KB |
Output is correct |
11 |
Correct |
3 ms |
21908 KB |
Output is correct |
12 |
Correct |
4 ms |
21852 KB |
Output is correct |
13 |
Correct |
4 ms |
21852 KB |
Output is correct |
14 |
Correct |
4 ms |
21848 KB |
Output is correct |
15 |
Correct |
3 ms |
21852 KB |
Output is correct |
16 |
Correct |
3 ms |
21848 KB |
Output is correct |
17 |
Correct |
4 ms |
21788 KB |
Output is correct |
18 |
Correct |
3 ms |
21848 KB |
Output is correct |
19 |
Correct |
3 ms |
21852 KB |
Output is correct |
20 |
Correct |
4 ms |
21852 KB |
Output is correct |
21 |
Correct |
3 ms |
21852 KB |
Output is correct |
22 |
Correct |
3 ms |
21852 KB |
Output is correct |
23 |
Correct |
4 ms |
21852 KB |
Output is correct |
24 |
Correct |
4 ms |
21952 KB |
Output is correct |
25 |
Correct |
4 ms |
21852 KB |
Output is correct |
26 |
Correct |
3 ms |
21976 KB |
Output is correct |
27 |
Correct |
4 ms |
21852 KB |
Output is correct |
28 |
Incorrect |
3 ms |
21852 KB |
Output isn't correct |
29 |
Halted |
0 ms |
0 KB |
- |