如何使用MPI_Scatterv将区块大小发送到特定进程？

#include <mpi.h>
#include <stdio.h>

int main(int argc, char** argv) {
    int rank, size;
    int sendcounts[4] = {1, 2, 3, 4}; // 每个进程接收的数据块大小
    int displs[4] = {0, 1, 3, 6}; // 每个进程接收数据块的偏移量
    int recvcount; // 接收到的数据块大小

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

    // 创建发送缓冲区和接收缓冲区
    int* sendbuf = NULL;
    int* recvbuf = NULL;
    if (rank == 0) {
        sendbuf = (int*)malloc(size * sizeof(int));
        for (int i = 0; i < size; i++) {
            sendbuf[i] = sendcounts[i];
        }
    }
    recvbuf = (int*)malloc(sizeof(int));

    // 使用MPI_Scatterv发送区块大小到特定进程
    MPI_Scatterv(sendbuf, sendcounts, displs, MPI_INT, recvbuf, 1, MPI_INT, 0, MPI_COMM_WORLD);

    // 打印接收到的数据块大小
    printf("Process %d received block size: %d\n", rank, *recvbuf);

    MPI_Finalize();
    return 0;
}