// ==================================================================
//      Author: Jean-Michel RICHER
//       Email: jean-michel.richer@univ-angers.fr
// Institution: LERIA, Faculty of Science 
//              University of Angers, France
// ==================================================================

#include <iostream>
#include <string>
#include <vector>
#include <numeric>
using namespace std;

/* ==================================================================
 * SUBPROGRAM
 *
 *		void share_elements(int N, int K, vector<int>& velems);
 *
 * WHAT
 *
 *  Distribute @param(N) elements over @param(K) processors
 *
 * HOW
 *
 *	Assume that the number of elements is well distributed over
 *  the processors
 *
 * PARAMETERS
 *
 *	@paramdef(int, N) : number of elements
 *  @paramdef(int, K) : number of processors / process / threads
 *  @paramdef(vector<int>&, velems) : vector that receives for each
 *			processor the number of elements it will have to treat
 *
 * ==================================================================
 */
void share_elements(int N, int K, vector<int>& velems) {
	
	int u_2 = N / K, left = N;

	int k;
	for (k = 0; k < K; ++k) {
		velems.push_back( u_2 );
		left -= u_2;
	}

	k = 0;
	while (left != 0) {
		++velems[ k ];
		--left;
		// here the '% K' is not necessary has there are left < K
		// elements to place
		k = (k + 1 ) % K;
	}
}

/* ==================================================================
 * SUBPROGRAM
 *
 * 		int main(int argc, char *argv[])
 *
 * WHAT
 *
 *   Main program
 *
 * PARAMETERS
 *
 *	@paramdef(int,argc) : number of command line arguments
 *  @paramdef(char **, argv) : command line arguments as C-strings
 *
 * ==================================================================
 */
int main(int argc, char *argv[]) {
	
	// Number of elements, i.e. size of an array
	int N = 105;
	// Number of processors / process / threads
	int K = 6;
	
	if (argc > 1) N = atoi( argv[1] );
	if (argc > 2) K = atoi( argv[2] );
	
	vector<int> v_nbr_elements;
	share_elements( N, K, v_nbr_elements );
	
	cout << "-------------------" << endl;
	for (int k = 0; k < K; ++k) {	
		cout << "k=" << k << ", #elements=" << v_nbr_elements[ k ] << endl;
	}
	
	int sum = accumulate( v_nbr_elements.begin(),
		v_nbr_elements.end(),
		0);
		
	cout << "-------------------" << endl;
	cout << "sum=" << sum << endl;
	cout << "-------------------" << endl;
	
	
	return EXIT_SUCCESS;
	
}