P17081 [GeeksforGeeks] Number of occurrence2259
普及
题目描述

Given a sorted array Arr of size N and a number X, you need to find the number of occurrences of X in Arr.
Example 1:
Input:
N = 7, X = 2
Arr[] = {1, 1, 2, 2, 2, 2, 3}
Output: 4
Explanation: 2 occurs 4 times in the
given array.
Example 2:
Input:
N = 7, X = 4
Arr[] = {1, 1, 2, 2, 2, 2, 3}
Output: 0
Explanation: 4 is not present in the
given array.
Your Task:
You don't need to read input or print anything. Your task is to complete the function count() which takes the array of integers arr, n, and x as parameters and returns an integer denoting the answer.
If x is not present in the array (arr) then return 0.
Expected Time Complexity: O(logN)
Expected Auxiliary Space: O(1)
Constraints:
1 ≤ N ≤ 10^{5}
1 ≤ Arr[i] ≤ 10^{6}
1 ≤ X ≤ 10^{6}

输入格式

见题面

输出格式

见题面

样例输入
N = 7, X = 2 Arr[] = {1, 1, 2, 2, 2, 2, 3}
样例输出
4