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c_cpp
a year ago
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#include <bits/stdc++.h>

using i64 = long long;

std::vector<int> minp, primes;

void sieve(int n) {
    minp.assign(n + 1, 0);
    primes.clear();
    
    for (int i = 2; i <= n; i++) {
        if (minp[i] == 0) {
            minp[i] = i;
            primes.push_back(i);
        }
        
        for (auto p : primes) {
            if (i * p > n) {
                break;
            }
            minp[i * p] = p;
            if (p == minp[i]) {
                break;
            }
        }
    }
}


int main() {
    std::ios::sync_with_stdio(false);
    std::cin.tie(nullptr);
    
    int n, k;
    std::cin >> n >> k;
    
    sieve(n);
    
    int cnt = 0;
    for (int i = 1; i < primes.size(); i++) {
        int x = primes[i - 1] + primes[i] + 1;
        if (x <= n && minp[x] == x) {
            cnt += 1;
        }
    }
    if (cnt >= k) {
        std::cout << "YES\n";
    } else {
        std::cout << "NO\n";
    }
    
    return 0;
}
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