# 1570. Dot Product of Two Sparse Vectors

Given two sparse vectors, compute their dot product.

Implement class `SparseVector`:

• `SparseVector(nums)` Initializes the object with the vector `nums`
• `dotProduct(vec)` Compute the dot product between the instance of SparseVector and `vec`

A sparse vector is a vector that has mostly zero values, you should store the sparse vector efficiently and compute the dot product between two SparseVector.

Follow up: What if only one of the vectors is sparse?

Example 1:

`Input: nums1 = [1,0,0,2,3], nums2 = [0,3,0,4,0]Output: 8Explanation: v1 = SparseVector(nums1) , v2 = SparseVector(nums2)v1.dotProduct(v2) = 1*0 + 0*3 + 0*0 + 2*4 + 3*0 = 8`

Example 2:

`Input: nums1 = [0,1,0,0,0], nums2 = [0,0,0,0,2]Output: 0Explanation: v1 = SparseVector(nums1) , v2 = SparseVector(nums2)v1.dotProduct(v2) = 0*0 + 1*0 + 0*0 + 0*0 + 0*2 = 0`

Example 3:

`Input: nums1 = [0,1,0,0,2,0,0], nums2 = [1,0,0,0,3,0,4]Output: 6`

Constraints:

• `n == nums1.length == nums2.length`
• `1 <= n <= 10^5`
• `0 <= nums1[i], nums2[i] <= 100`