#include <bits/stdc++.h>
#define pb push_back
using namespace std;
typedef long long ll;
vector <int> adj[1001];
int a, b;
bool check(int x) {
if (x == 0) return false;
if (x == 1) return false;
if (x == 2) return true;
for (int i = 2; i <= sqrt(x); ++ i)
if (x % i == 0) return false;
return true;
}
queue <int> q;
bool ok[1001];
int par[1001];
void bfs() {
ok[a] = true;
q.push(a);
while (!q.empty()) {
int u = q.back();
q.pop();
for (int v : adj[u]) {
if (ok[v] == false) {
par[v] = u;
ok[v] = true;
q.push(v);
}
}
}
}
int d[3] = {0, 2, -2};
int main() {
//freopen(".INP", "r", stdin);
//freopen(".OUT", "w", stdout);
ios_base::sync_with_stdio(false);
cin.tie(NULL); cout.tie(NULL);
memset(ok, false, sizeof(ok));
cin >> a >> b;
for (int i = 0; i < 3; ++ i) {
for (int j = 0; j < 3; ++ j) {
int u = a + d[i], v = b + d[j];
if (check(u) == false || check(v) == false) continue;
// cout << u << " " << v << endl;
if (u > 0 && v > 0 && check(abs(v - u))) {
adj[u].pb(v);
adj[v].pb(u);
}
}
}
for (int j = 0; j < 3; ++ j) {
if (a + d[j] > 0 && check(a + d[j])) {
adj[a].pb(a + d[j]);
adj[a + d[j]].pb(a);
}
if (b + d[j] > 0 && check(b + d[j])) {
adj[b].pb(b + d[j]);
adj[b + d[j]].pb(b);
}
}
bfs();
if (ok[b]) {
vector <int> ans;
ans.pb(b);
while (par[b] != 0) {
ans.pb(par[b]);
b = par[b];
}
cout << ans.size() << "\n";
for (int i = ans.size() - 1; i >= 0; -- i) cout << ans[i] << " ";
return 0;
}
cout << -1;
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
384 KB |
Output is correct |
2 |
Incorrect |
1 ms |
384 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
384 KB |
Output is correct |
2 |
Incorrect |
1 ms |
512 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
1 ms |
384 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
1 ms |
384 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
1 ms |
512 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
1 ms |
384 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
3 ms |
512 KB |
Execution killed with signal 11 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
3 ms |
512 KB |
Execution killed with signal 11 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
3 ms |
512 KB |
Execution killed with signal 11 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
3 ms |
512 KB |
Execution killed with signal 11 |
2 |
Halted |
0 ms |
0 KB |
- |