Consider the following two-dimensional array:
int X[64][64];
Suppose that a system has four page frames and each frame is 128 words (an integer occupies one word). Programs that manipulate the X array fit into exactly one page and always occupy page 0. The data are swapped in and out of the other three frames. The X array is stored in row-major order (i.e., X[0][1] follows X[0][0] in memory). Which of the two code fragments shown below will generate the lowest number of page faults? Explain and compute the total number of page faults.
Fragment A
for (int j = 0; j < 64; j++)
for (int i = 0; i < 64; i++) X[i][j] = 0;
Fragment B
for (int i = 0; i < 64; i++)
for (int j = 0; j < 64; j++) X[i][j] = 0;