void AsSortbyName(char name[][20], float score[], int n)
{
    int i, j, t;
    for(i=0;i<n-1;i++)
    {
        for(j=i+1;j<n;j++)
        {
            if(strcmp(name[j],name[i])<0)
            {
                t = i;
                i = j;
                j = t;
            }
        }
    }
    printf("Sort in ascending order by name:");
    for(i=0; i<n; i++)
        printf("%f", score[i]);
    printf("\n");
}

最好把调用的也贴出来，另外楼主在交换两个元素的方法不对吧，哪有这么写的