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更多“I couldn ’t tell _____ whether he had left or not. ”相关问题
  • 第1题:

    He ( ) so hurriedly that day, actually there was still more than half an hour left.

    A、oughtn't to leave

    B、needn't have left

    C、needn’t leave

    D、couldn’t leave


    参考答案:B

  • 第2题:

    I _______ him study hard until he passes the exam.

    A.ask

    B.made

    C.let

    D.had


    参考答案:C

  • 第3题:

    阅读下列C程序和程序说明,将应填入(n)处的字句写在对应栏内。

    【说明】下面是一个用C编写的快速排序算法。为了避免最坏情况,取基准记录pivot时,采用从left、right和mid=[(left+right)/2]中取中间值,并交换到right位置的办法。数组a存放待排序的一组记录,数据类型为T,left和right是待排序子区间的最左端点和最右端点。

    void quicksort (int a[], int left, int right) {

    int temp;

    if (left<right) {

    hat pivot = median3 (a, left, right); //三者取中子程序

    int i = left, j = right-1;

    for(;;){

    while (i <j && a[i] < pivot) i++;

    while (i <j && pivot < a[j]) j--;

    if(i<j){

    temp = a[i]; a[j] = a[i]; a[i] = temp;

    i++; j--;

    }

    else break;

    }

    if (a[i] > pivot)

    {temp = a[i]; a[i] = a[right]; a[right] = temp;}

    quicksort( (1) ); //递归排序左子区间

    quieksort(a,i+1 ,right); //递归排序右子区间

    }

    }

    void median3 (int a[], int left, int right)

    { int mid=(2);

    int k = left;

    if(a[mid] < a[k])k = mid;

    if(a[high] < a[k]) k = high; //选最小记录

    int temp = a[k]; a[k] = a[left]; a[left] = temp; //最小者交换到 left

    if(a[mid] < a[right])

    {temp=a[mid]; a[mid]=a[right]; a[right]=temp;}

    }

    消去第二个递归调用 quicksort (a,i+1,right)。 采用循环的办法:

    void quicksort (int a[], int left, int right) {

    int temp; int i,j;

    (3) {

    int pivot = median3(a, left, right); //三者取中子程序

    i = left; j = righi-1;

    for (;; ){

    while (i<j && a[i] < pivot)i++;

    while (i<j && pivot <a[j]) j--;

    if(i <j) {

    temp = a[i]; a[j]; = a[i]; a[i]=temp;

    i++; j--;

    }

    else break;

    }

    if(a[i]>pivot){(4);a[i]=pivot;}

    quicksoft ((5)); //递归排序左子区间

    left = i+1;

    }

    }


    正确答案:(1)alefti-1 (2)(left+right+1)/2 (3)while(leftright) (4)a[right)=a[i] (5)aleft i-1
    (1)a,left,i-1 (2)(left+right+1)/2 (3)while(leftright) (4)a[right)=a[i] (5)a,left, i-1 解析:(1)a,left,i-1
    递归排序左子区间,从left到i-1元素,不包括i元素。
    (2)(left+right+1)/2
    三者取中子程序median3(a,left,right),取基准记录pivot时,采用从left、right和 mid=[(left+right)/2]中取中间值,并交换到right位置的办法。
    (3)while(leftright)
    循环直到left和right相遇。
    (4)a[right)=a[i]
    若a[i]>pivot则让a[right]=a[i]而让a[i]=pivot;。
    (5)a,left, i-1
    递归排序左子区间,从left到i-1元素,不包括i元素。

  • 第4题:

    --Your phone number again? I _______ quite catch it.

    A.don't

    B.can't

    C.couldn't

    D.didn't


    参考答案:D

  • 第5题:

    He__me he was leaving on Wednesday.

    A. said

    B. told

    C. tell


    参考答案B

  • 第6题:

    – Do you agree with me? -- ______________.

    A、No.

    B、I’m afraid not.

    C、I can’t.

    D、Not.


    正确答案:B