#include <bits/stdc++.h>
#define FOR(i, x, y) for (int i = x; i < y; i++)
typedef long long ll;
using namespace std;
vector<ll> stck;
map<ll, bool> visited;
ll a, b;
bool found = false;
bool is_prime(ll n) {
if (n < 2) return false;
FOR(i, 2, sqrt(n) + 1) if (n % i == 0) return false;
return true;
}
void dfs(ll node) {
if (found) return;
stck.push_back(node);
visited[node] = true;
if (node == b) {
cout << stck.size() << '\n';
for (ll i : stck) cout << i << ' ';
found = true;
return;
}
if (is_prime(node + 2) && !visited[node + 2]) dfs(node + 2);
if (is_prime(node - 2)) {
if (!visited[node - 2]) dfs(node - 2);
if (!visited[2]) dfs(2);
}
if (is_prime(b - node)) dfs(b);
if (is_prime(b - 2) && is_prime(b - node - 2)) dfs(b - 2);
if (is_prime(b + 2) && is_prime(b - node + 2)) dfs(b + 2);
stck.pop_back();
}
int main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
cin >> a >> b;
dfs(a);
if (!found) cout << -1;
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
376 KB |
Output is correct |
2 |
Correct |
2 ms |
376 KB |
Output is correct |
3 |
Correct |
2 ms |
380 KB |
Output is correct |
4 |
Correct |
2 ms |
376 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
376 KB |
Output is correct |
2 |
Correct |
2 ms |
376 KB |
Output is correct |
3 |
Correct |
2 ms |
420 KB |
Output is correct |
4 |
Correct |
2 ms |
376 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
376 KB |
Output is correct |
2 |
Correct |
2 ms |
380 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
376 KB |
Output is correct |
2 |
Correct |
2 ms |
376 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
416 KB |
Output is correct |
2 |
Correct |
2 ms |
252 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
252 KB |
Output is correct |
2 |
Correct |
2 ms |
376 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
978 ms |
376 KB |
Output is correct |
2 |
Correct |
126 ms |
376 KB |
Output is correct |
3 |
Correct |
245 ms |
380 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
800 ms |
376 KB |
Output is correct |
2 |
Correct |
124 ms |
376 KB |
Output is correct |
3 |
Correct |
180 ms |
376 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
859 ms |
508 KB |
Output is correct |
2 |
Correct |
123 ms |
412 KB |
Output is correct |
3 |
Correct |
167 ms |
376 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
512 ms |
384 KB |
Output is correct |
2 |
Correct |
92 ms |
380 KB |
Output is correct |
3 |
Correct |
62 ms |
504 KB |
Output is correct |