28 lines
687 B
C++
28 lines
687 B
C++
#include <bits/stdc++.h>
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using namespace std;
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const int N = 1e5 + 10;
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// 线性筛法求素数 （简称 欧拉筛）
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int primes[N], cnt;
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bool st[N];
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void get_primes(int n) {
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for (int i = 2; i <= n; i++) {
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if (!st[i]) primes[cnt++] = i;
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for (int j = 0; primes[j] * i <= n; j++) {
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st[primes[j] * i] = true;
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if (i % primes[j] == 0) break;
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}
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}
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}
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int L, ans, sum;
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int main() {
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cin >> L;
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get_primes(L);
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for (int i = 0; i < cnt; i++) {
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if (ans + primes[i] > L) break;
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ans += primes[i];
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printf("%d\n", primes[i]);
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sum++;
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}
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printf("%d\n", sum);
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return 0;
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} |