Having done WA3 and PA3 I think one important application that was overlooked was the use of the prefix sum to compress information in arrays. For example, we used the prefix sum to reduce an array of elements A into an array that shows the just the repeats where A[i]==A[i+1]. And in another example we used the prefix sum to reduce an array of boolean values into an array that shows the size of segments.
Having done WA3 and PA3 I think one important application that was overlooked was the use of the prefix sum to compress information in arrays. For example, we used the prefix sum to reduce an array of elements A into an array that shows the just the repeats where A[i]==A[i+1]. And in another example we used the prefix sum to reduce an array of boolean values into an array that shows the size of segments.