- Draw a flow chart for the Factors.java program. Here is an example of a flowchart with all the shapes your flow chart should have:
Another good flowchart example:
You can draw flowcharts if you create an account here
- Tracing 101: Draw (on paper or doc ) a table of values for the variables “factor” and “n” for the following test data:
- A table for input: 27
- A table for input: 42
- A table for input: 29
3. Modify Factors.java to print just one copy of each of the prime divisors. ModFactors_YI.java
[spoiler title=’Factors.java’]
/******************************************************************************
* Compilation: javac Factors.java
* Execution: java Factors n
*
* Computes the prime factorization of n using brute force.
*
* % java Factors 81
* The prime factorization of 81 is: 3 3 3 3
*
* % java Factors 168
* The prime factorization of 168 is: 2 2 2 3 7
*
* % java Factors 4444444444
* The prime factorization of 4444444444 is: 2 2 11 41 271 9091
*
* % java Factors 4444444444444463
* The prime factorization of 4444444444444463 is: 4444444444444463
*
* % java Factors 10000001400000049
* The prime factorization of 10000001400000049 is: 100000007 100000007
*
* % java Factors 1000000014000000049
* The prime factorization of 1000000014000000049 is: 1000000007 1000000007
*
* % java Factors 9201111169755555649
* The prime factorization of 9201111169755555649 is: 3033333343 3033333343
*
* Can use these for timing tests - biggest 3, 6, 9, 12, 15, and 18 digit primes
* % java Factors 997
* % java Factors 999983
* % java Factors 999999937
* % java Factors 999999999989
* % java Factors 999999999999989
* % java Factors 999999999999999989
*
* Remarks
* -------
* - Tests factor*factor <= n instead of factor <= n for efficiency.
*
* - The last two examples still take a few minutes.
*
******************************************************************************/
public class Factors {
public static void main(String[] args) {
// command-line argument
long n = Long.parseLong(args[0]);
System.out.print("The prime factorization of " + n + " is: ");
// for each potential factor
for (long factor = 2; factor*factor <= n; factor++) {
// if factor is a factor of n, repeatedly divide it out
while (n % factor == 0) {
System.out.print(factor + " ");
n = n / factor;
}
}
// if biggest factor occurs only once, n > 1
if (n > 1) System.out.println(n);
else System.out.println();
}
}
[/spoiler]
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