使用C++中的排序运算符<定义MPI

#include <mpi.h>
#include <iostream>

bool customCompare(int a, int b) {
    // 自定义排序规则，按照数字的绝对值进行排序
    return abs(a) < abs(b);
}

int main(int argc, char** argv) {
    MPI_Init(&argc, &argv);

    int rank, size;
    MPI_Comm_rank(MPI_COMM_WORLD, &rank);
    MPI_Comm_size(MPI_COMM_WORLD, &size);

    int data[size] = {4, -2, 7, -5, 1};

    // 使用排序运算符<定义MPI
    MPI_Datatype customType;
    MPI_Type_contiguous(sizeof(int), MPI_BYTE, &customType);
    MPI_Type_commit(&customType);
    MPI_Op customOp;
    MPI_Op_create((MPI_User_function*)customCompare, 1, &customOp);

    // 进行排序
    MPI_Allreduce(MPI_IN_PLACE, data, size, customType, customOp, MPI_COMM_WORLD);

    // 输出排序结果
    if (rank == 0) {
        std::cout << "Sorted data: ";
        for (int i = 0; i < size; i++) {
            std::cout << data[i] << " ";
        }
        std::cout << std::endl;
    }

    MPI_Op_free(&customOp);
    MPI_Type_free(&customType);
    MPI_Finalize();

    return 0;
}