Description

Discussing the Fundamental Concepts of Recursion [CO 5]

Instructions:

Task 1
Simulate, write code and show final output for Binary Searching
I. Using Iterative method
II. Using Recursive method
[Take an array of your choosing for showing simulations and final output]

Task 2
Write a recursive program which sums the first ten positive numbers and simulate your code for any input.

Task 3
Trace the following Code showing each step. What will be the output?

public class fibonacci {

static int fib(int n) {
if (n <= 1){ return n;
}
else{
return fib(n-1) + fib(n-2);
}
}

} public static void main (String args[]) { int n = X; // X={(last 4 digit of your id%3)+ (last 3 digit of your id%4)+2} System.out.println(fib(n));
}
Task 4

Trace the following Code showing each step. What will be the output?

// Java program to find factorial of given number

public class Test
{
// method to find factorial of given number static int factorial(int n) {
if (n == 0) { return 1;
}else{
return n*factorial(n-1);
}
}

}

// Driver method
public static void main(String[] args) { int num = X; // X={(last 4 digit of your id%3)+ (last 3 digit of your id%4)+2}
System.out.println(“Factorial of “+ num + ” is ” + factorial(num));
}

Task 5
Trace the following Code showing each step. What will be the output?

public class Test{

/* Function to calculate x raised to the power y */ static int power(int x, int y) {
if (y == 0){ return 1;
}else if (y % 2 == 0){
return power(x, y / 2) * power(x, y / 2);
}else{
return x * power(x, y/2) * power(x, y/2);
}
}
/* Program to test function power */

public static void main(String[] args) { int x = {last 4 digit of your id%5)+2};

int y = {last 3 digit of your
id%3)+1};

System.out.printf(“%d”,
power(x, y));
} }
Task 6

public static int mystery3(int n) { if (n < 0){
return -mystery3(-n);
}else if (n < 10){ return n;
}else{ return mystery3(n/10 + n % 10);
}
}

For each call below, indicate what value is returned with showing the steps:
mystery3(6)
mystery3(17)

mystery3(259)

mystery3(-479)

Task 7

public static void mystery4(String s) { if (s.length() > 0) {
System.out.print(s.charAt(0));
if (s.length() % 2 == 0){
mystery4(s.substring(0, s.length() -1));
}
else{
System.out.println(“**”);
System.out.println(“#”+ s.length()+ s.length()+”*”); mystery4(s.substring(1, s.length())); System.out.print(s.charAt(s.length() – 1));
}
}
}

For each call below, indicate what output is printed with showing the steps:
mystery4(“”)
mystery4(“a”) mystery4(“ab”) mystery4(“bc”)

mystery4(“abcd”)