A two-dimensional array operation problem

main()
{
    int a[3][4]={1,2,3,4,5,6,7,8,9,10,11,12};
    int i,(*b)[4];
    for(i=0;i<2;i++)
    {
        b=a+i;
        printf("%d",*(b[i]+1));
        printf("\n");
    }
}

Answer: 2,10