剑指offer刷题总结——数组篇（五）

1.数字在排序数组中出现的次数

【题目】

统计一个数字在排序数组中出现的次数。

【代码】

public int GetNumberOfK(int [] array , int k) {
   

        if (array.length==0 || array==null) return 0;

        int i,n,count;
        n = array.length;

        count = 0;
        for (i=0; i<n; i++) {
   
            if (array[i] == k) count++;
        }

        return count;
    }

    public int high(int[] a, int k) {
   
        int start,end,mid;

        start = 0;
        end = a.length-1;

        while (start <= end) {
   
            mid = (start + end) >> 1;
            if (a[mid] <= k) {
   
                start = mid + 1;
            } else {
   
                end = mid - 1;
            }
        }

        return end;
    }

    public int low(int[] a, int k) {
   
        int start,end,mid;

        start = 0;
        end = a.length-1;

        while (start <= end) {
   
            mid = (start + end) >> 1;
            if (a[mid]