Enter: A = 1 B = 7 Enter: A = 1 B = 3 Leave: A = 1 B = 3 Leave: A = 1 B = 7 2
6 2 7 1 8 0 8 0 7 1 6 2
This recursive function produces no output. The recursive calls made are: f(6,8); f(6,2); f(4,2); f(2,2); The output: 2
F entered with N = 8 F entered with N = 6 F entered with N = 4 F entered with N = 2 F entered with N = 0 F entered with N = 2 F entered with N = 4 F entered with N = 2 F entered with N = 0 F(8) = 27 N < 0 or N = 3 will result in an infinite recursion.
// Returns the sum of the first N integers in the array A.
public static int ComputeSum(int A[], int N) {
if(N <= 0)
return 0;
else
// reduce the problem size
return A[N - 1] + ComputeSum(A, N - 1);
}
// Prints out the integers from 1 through N as a
// comma separated list followed by a newline.
public static void PrintIntegers(int N, int Limit) {
if(N > 0) {
// print out the rest of the integers then print out this integer
PrintIntegers(N - 1, Limit);
System.out.print(N);
// test for end of string
if(N != Limit)
System.out.print(", ");
else
System.out.println(".");
}
// N <= 0 do nothing;
}
// Outputs a line of N characters where Ch is the character.
public static void WriteLine(char Ch, int N) {
if(N <= 0)
System.out.println();
// write rest of line
else {
System.out.print(Ch);
WriteLine(Ch, N - 1);
}
}
// Outputs a block of M rows by N columns of character Ch.
public static void WriteBlock(char Ch, int M, int N) {
if(M > 0) {
// write first line then write rest of block
WriteLine(Ch, N);
WriteBlock(Ch, M - 1, N);
}
// base case: M <= 0 do nothing.
}
- For a binary search to work the array must first be sorted
- Index = (0 + 101)/2 = 50
- Number of comparisons = 7
static int numEvens(LLNode<Integer> list) {
if (list == null)
return 0;
else
if ((list.getInfo() % 2) == 0)
return 1 + numEvens(list.getLink());
else
return numEvens(list.getLink());
}
static boolean contains(int target, LLNode<Integer> list) {
if (list == null)
return false;
else
if (list.getInfo() == target)
return true;
else
return contains(target, list.getLink());
}
-
call 1: str "abcba" result false str.length() = 5 str.charAt(0) = 'a' str.charAt(4) = 'a' | ^ | | | | return true v | call 2: str "bcb" result false str.length() = 3 str.charAt(0) = 'b' str.charAt(4) = 'b' | ^ | | | | return true v | call 3: str "c" result false str.length() = 1 result = true return true -
call 1: str "abcxycba" result false str.length() = 8 str.charAt(0) = 'a' str.charAt(7) = 'a' | ^ | | | | return false v | call 2: str "bcxycb" result false str.length() = 6 str.charAt(0) = 'b' str.charAt(5) = 'b' | ^ | | | | return false v | call 3: str "cxyc" result false str.length() = 4 str.charAt(0) = 'c' str.charAt(3) = 'c' | ^ | | | | return false v | call 4: str "xy" result false str.length() = 2 str.charAt(0) = 'x' str.charAt(1) = 'y' return false
Saturn
Jupiter
Mars
int linsearch(int[] arr, int value) {
return linsearch(arr,arr.length,value);
int linsearch(int[] arr, int size, int value) {
if (size == 0)
return -1;
else
if (arr[size-1] == value)
return size-1;
else
return linsearch(arr,size-1,value);
}
int numeven(int[] arr) {
return numeven(arr,arr.length);
int numeven(int[] arr, int size) {
if (size == 0)
return 0;
else
if (arr[size-1] % 2 == 0)
return 1 + numeven(arr,size-1);
else
return numeven(arr,size-1)
}
static int linsearch(int value, int[] nums) {
return linsearch(value, 0, nums);
}
static int linsearch(int value, int pos, int[] nums) {
if (pos == nums.length)
return -1;
else
if (nums[pos] == value)
return pos;
else
return linsearch(value, pos+1, nums);
}
static String rev(String revstr) {
int end = revstr.length() - 1;
if (end == 0)
return revstr;
else if (end == 1)
return revstr;
else {
System.out.println(revstr);
return revstr.charAt(end)
+ rev(revstr.substring(1,end))
+ revstr.charAt(0);
}
}