#include <vector>

#include "mpi.h"

using namespace std;

int main(int argc, char** argv)
{
    int n, a, b;
    n = atoi(argv[1]);
    a = atoi(argv[2]);
    b = atoi(argv[3]);

    int size, rank;
    MPI_Status status;
    MPI_Init(&argc, &argv);
    MPI_Comm_size(MPI_COMM_WORLD, &size);
    MPI_Comm_rank(MPI_COMM_WORLD, &rank);

    srand(rank);
    int blocksize = n / size;
    if (rank < n % size)
        ++blocksize;

    bool flag = true;
    bool proc_flag = true;
    int res = 0;
    int proc_res = 0;

    int arr[blocksize];
    for (int i = 0; i < block_size; ++i) {
        arr[i] = rand();
        if ((i > 0) && (arr[i - 1] > arr[i])) {
            proc_falg = false;
        }
        if (a <= arr[i] && arr[i] <= b) {
            ++proc_res;
        }
    }

    int bound;
    MPI_Request request1;
    MPI_Request request2;
    if (rank > 0) {
        MPI_Isend(arr[0], 1, MPI_INT, std::max(rank - 1, 0), 0, MPI_COMM_WORLD, &request1);
        MPI_Irecv(lb, 1, MPI_INT, std::max(rank - 1, 0), 0, MPI_COMM_WORLD, &request2);
        if (bound > arr[0]) {
            proc_flag = false;
        }
    }

    MPI_Reduce(&proc_res, &res, 1, MPI_INT, MPI_SUM, 0, MPI_COMM_WORLD);
    MPI_Reduce(&proc_flag, &flag, 1, MPI_BOOL, MPI_LAND, 0, MPI_COMM_WORLD);
    MPI_Finalize();

    if (rank == 0) {
        if (flag) {
            cout << res;
        } else {
            return -1;
        }
    }

    return 0;
}