Element Occurrence

Problem statement

Suppose we are given a sorted array of integers, find the number of occurrences of a given target value. If the target is not found in the array, return -1.

Constraints:

• $1 \leq nums.length \leq 10^4$
• $-10^4 \leq nums[i] \leq 10^4$
• $nums$ contains values sorted in an ascending order.
• $-10^4 \leq target \leq 10^4$

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