Prentice.Hall.Introduction.to.Java.Programming,.Brief.Version.9th.(2014).[sharethefiles.com]

4.6 Nested Loops 153
Note
Be aware that a nested loop may take a long time to run. Consider the following loop
nested in three levels:
for (int i = 0; i < 10000; i++)
for (int j = 0; j < 10000; j++)
for (int k = 0; k < 10000; k++)
Perform an action
The action is performed one trillion times. If it takes 1 microsecond to perform the action,
the total time to run the loop would be more than 277 hours. Note that 1 microsecond is
one millionth (10 –6 ) of a second.
4.19 How many times is the println statement executed?
for (int i = 0; i < 10; i++)
for (int j = 0; j < i; j++)
System.out.println(i * j)
✓Point✓ Check
4.20 Show the output of the following programs. (Hint: Draw a table and list the variables
in the columns to trace these programs.)
public class Test {
/** Main method */
public static void main(String[] args) {
for (int i = 1; i < 5; i++) {
int j = 0;
while (j < i) {
System.out.print(j + " ");
j++;
}
}
}
}
(a)
public class Test {
/** Main method */
public static void main(String[] args) {
int i = 0;
while (i < 5) {
for (int j = i; j > 1; j——)
System.out.print(j + " ");
System.out.println("****");
i++;
}
}
}
(b)
public class Test {
public static void main(String[] args) {
int i = 5;
while (i >= 1) {
int num = 1;
for (int j = 1; j