61 lines
1.4 KiB
C++
61 lines
1.4 KiB
C++
#include <bits/stdc++.h>
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using namespace std;
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int MAXN = 1000;
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vector<int> genPrimes(int n){
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vector<bool> primeBinary(n+1, true);
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for(int i = 2; i <= n; ++i){
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if(primeBinary[i]){
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for(int j = 2 * i; j <= n; j += i){
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primeBinary[j] = false;
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}
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}
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}
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vector<int> result;
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for(int i = 2; i <= n; ++i){
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if(primeBinary[i]){
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result.push_back(i);
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}
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}
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return result;
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}
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int main(){
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cout << "Hello this is Patrick" << endl;
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auto start = chrono::high_resolution_clock::now();
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auto primes = genPrimes(MAXN);
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set<int> primeSet(primes.begin(), primes.end());
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vector<unsigned long long> solutions(MAXN + 1, 0);
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solutions[0] = 1;
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for(int i = 2; i <= MAXN; ++i){
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if(primeSet.count(i)){
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for(int pos = 0; pos <= MAXN - i; ++pos){
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solutions[pos + i] += solutions[pos];
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}
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}
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}
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for(int i = 0; i < solutions.size(); ++i){
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// cout << solutions[i] << " ";
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if(solutions[i] > 5000){
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cout << i << endl;
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break;
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}
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}
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auto duration = chrono::duration_cast<chrono::milliseconds>(chrono::high_resolution_clock::now() - start);
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cout << (float)duration.count()/1000 << endl;
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return 0;
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}
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