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38 lines
650 B
C++
38 lines
650 B
C++
#include <bits/stdc++.h>
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using namespace std;
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bool isPrime(int x) {
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if (x == 1) {
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return false;
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}
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if (x == 2) {
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return true;
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}
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if (x % 2 == 0) {
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return false;
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}
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for (int i = 2; i * i <= x; i++) {
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if (x % i == 0) {
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return false;
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}
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}
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return true;
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}
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int main() {
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int n, k;
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bool flag = false;
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cin >> n >> k;
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for (int i = 2; i + k <= n; i++) {
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if (isPrime(i) && isPrime(i + k)) {
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cout << i << ' ' << i + k << endl;
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flag = true;
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}
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}
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if (!flag) {
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cout << "empty" << endl;
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}
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return 0;
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}
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