#include "task_3.h"
#include "mayer_primes.h"
#include "timing.h"

#include <algorithm>
#include <cassert>
#include <iostream>
#include <omp.h>
#include <vector>
using namespace std;


int single_goldbach_par(int k) {
    const vector<int> primes = get_primes(k);
    int count = 0;

    #pragma omp parallel for reduction(+:count)
    for (size_t i = 0; i < primes.size(); i++) {
        for (size_t j = i; j < primes.size(); j++) {
            if (primes[i] + primes[j] == k) {
                count++;
            }
        }
    }

    return count;
}


vector<int> count_goldbach_par(int n) {
    const vector<int> primes = get_primes(n);
    vector<int> counts(n+1);

    #pragma omp parallel reduction(VecAdd:counts)
    // #pragma omp parallel
    {
        vector<int> local_counts(n+1, 0);

            #pragma omp for
        for (size_t i = 1; i < primes.size(); i++) {
            for (size_t j = i; j < primes.size(); j++) {
                int sum = primes[i] + primes[j];
                if (sum <= n) {
                    local_counts[sum]++;
                }
            }
        }

        counts += local_counts;
        // #pragma omp critical
        // {
        //     for(int k=0; k<n+1; k++){
        //     counts[k] += local_counts[k];
        //     }
        // }
    }
    return counts;
}


void print_decomps(int k) {
    const vector<int> primes = get_primes(k);
    cout << "\nDecompositions for k = " << k << ": ";

    for (size_t i = 0; i < primes.size(); i++) {
        for (size_t j = i; j < primes.size(); j++) {
            if (primes[i] + primes[j] == k) {
                cout << primes[i] << " + " << primes[j] << ", ";
            }
        }
    }
    cout << endl;
}