The following program subtracts 25 from the value of R1 and

The following program subtracts 25 from the value of R1 and store the result in location x5000. .ORIG x3000 ADD R0, R1, #0 ADD R0, R0, #-15 ADD R0, R0, #-10 STI R0, PTR HALT PTR FILL x5000 END Why are there two \'ADD\' instructions in the program? (The two \'ADD\' instructions being referred here, and marked in bold text) Suppose that the above program is written as two separate programs P1 and P2, as shown below. Will the assembly of P1 be successful? Why? .ORIG x3000 ADD R0, R1, #0 ADD R0, R0, #-15 ADD R0, R0, #-10 STI R0, PTR HALT END P2; PTR .FILL x5000 .END How should we modify P1 such that P1 and P2 can be assembled to form a single executable? What is used to combine these two programs?

Solution

public final class RotateNinetyInPlace { private RotateNinetyInPlace() {} private static void transpose(int[][] m) { for (int i = 0; i < m.length; i++) { for (int j = i; j < m[0].length; j++) { int x = m[i][j]; m[i][j] = m[j][i]; m[j][i] = x; } } } public static void rotateByNinetyToLeft(int[][] m) { // transpose transpose(m); // swap rows for (int i = 0; i < m.length/2; i++) { for (int j = 0; j < m[0].length; j++) { int x = m[i][j]; m[i][j] = m[m.length -1 -i][j]; m[m.length -1 -i][j] = x; } } } public static void rotateByNinetyToRight(int[][] m) { // transpose transpose(m); // swap columns for (int j = 0; j < m[0].length/2; j++) { for (int i = 0; i < m.length; i++) { int x = m[i][j]; m[i][j] = m[i][m[0].length -1 -j]; m[i][m[0].length -1 -j] = x; } } } public static void main(String[] args) { int[][] mEven = {{1, 3}, {2, 4}}; rotateByNinetyToLeft(mEven); for (int i = 0; i < mEven.length; i++) { for (int j = 0; j < mEven[0].length; j++) { System.out.print(mEven[i][j] + \" \"); } System.out.println(); } System.out.println(\"---------------------------------\"); rotateByNinetyToRight(mEven); for (int i = 0; i < mEven.length; i++) { for (int j = 0; j < mEven[0].length; j++) { System.out.print(mEven[i][j] + \" \"); } System.out.println(); } System.out.println(\"---------------------------------\"); int[][] mOdd = {{1, 2, 3}, {4, 5, 6}, {7, 8, 9}}; rotateByNinetyToLeft(mOdd); for (int i = 0; i < mOdd.length; i++) { for (int j = 0; j < mOdd[0].length; j++) { System.out.print(mOdd[i][j] + \" \"); } System.out.println(); } System.out.println(\"---------------------------------\"); rotateByNinetyToRight(mOdd); for (int i = 0; i < mOdd.length; i++) { for (int j = 0; j < mOdd[0].length; j++) { System.out.print(mOdd[i][j] + \" \"); } System.out.println(); } System.out.println(\"---------------------------------\"); } }