Below is a code snippet that is run in a system using a cache with a size of 256 Bytes and a data object (line width) of 64 Bytes. The array holds 4-byte integer values.

for (int j = 0; j < step; j++) {

for (int i = 0; i < 128/step; i++) {

A[i * step + j] = j;

}

}

In a system with a directly mapped (direct-mapped) cache structure, find the step values that make the cache hit rate (the rate of finding the searched data in the cache) the highest and lowest.