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- #include<bits/stdc++.h>
-
- using namespace std;
- using LL=long long;
- const int MAXN = 1e6 + 10;
- vector<int> primes = {2, 3};
-
- void init() {
- for (int k = primes.back(); k <= MAXN; k += 2) {
- bool flag = true;
- for (auto p:primes) {
- if (p * p > k)break;
- if (k % p == 0) {
- flag = false;
- break;
- }
- }
- if (flag)primes.push_back(k);
- }
- }
-
- int main() {
- init();
- for (int n; cin >> n;) {
- int p = n >> 1;
- if ((p & 1) == 0)--p;
- for (; p >= 3; p -= 2) {
- if (binary_search(primes.begin(), primes.end(), p) and binary_search(primes.begin(), primes.end(), n - p)) {
- cout << p << " " << n - p << endl;
- break;
- }
- }
-
- }
- return 0;
- }
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