08 - F Advanced.md

✨ F Advanced ✨

Define a function

1. that when passed an integer array, returns the number of even numbers.
2. that when passed an integer (assume it's positive), returns an array containing those many items.
3. that when passed two integer arrays, returns true if they are IDENTICAL, false otherwise. For example, {10, 70, 20, 90} is identical to {10, 70, 20, 90} but not identical to either of {10, 70, 90, 20}, or {10, 70, 20}, or {10, 70, 20, 90, 30}.
4. that when passed an integer array holding 0 or more items, returns true if it's sorted in ascending order (each item must be greater than or equal to the preceding item), false otherwise. Arrays of size less than 2 are considered as sorted by default.

What is the output of the following code?

int foo(int n) {
  int result = n*n;
  println(result);
  return result;
}

int bar(int n) {
  int result = foo(n) + foo(n+1);
  println(result);
  return result;
}

int tip(int n) {
  int result = bar(n) - bar(n-2);
  println(result);
  return result;
}

void setup() {
  println(tip(3));
}

What is the number is printed on execution of the following code?

int foo(int n) {
  if (n < 1) {
    return 0;
  } else if (n == 1) {
    return 1;
  }
  return n + foo(n - 1);
}

void setup() {
  print(foo(7));
  print(foo(-2));
}

Define a function called indexInArray

that when passed in a one-dimensional integer array called arr and an integer num returns the index of the first occurence of num in arr. If the integer num does not exist in arr, return -1.

Some examples:

• indexInArray({1, 5, 3, 10}, 10) returns 3
• indexInArray({8, 2, 5, 19, 3, 3, 4}, 3) returns 4

Define a function called isIdentityMatrix

that when passed in a two-dimensional float array called arr returns:

• true if it is an Identity matrix
• false otherwise

An Identity matrix is a matrix with equal rows and colomns and contains ones in the diagonals and zeroes everywhere else. The one shown below is a 3 by 3 Identity Matrix:

Some examples:

• isIdentityMatrix({{1, 0}, {0, 1}}) returns true
• isIdentityMatrix({{1, 0}, {1}}) returns false
• isIdentityMatrix({{1, 0, 0}, {0, 1, 0}, {0, 0, 1}}) returns true
• isIdentityMatrix({{1, 0, 0}, {0, 1, 0}, {0, 1, 1}}) returns false
• isIdentityMatrix({{1, 0, 0}, {0, 1, 0}}) returns false

What is the console output of the following code?

Include your working for partial marks

void setup() {
    println(foo(4));
}

int foo(int n) {
    if (n < 1) {
        return 1;
    }

    return n * foo(n - 1);

}

Describe what the user sees during the execution of the following program.

Please describe execution in as much detail as you can, avoiding the use of technical terminology (e.g state "a large white circle in the top right of the screen" as opposed to "a white ellipse of radius 500 centred at co-ordinates (300, 50)).

float dia = 10;
float maxBrightness = 200;

void setup() {
  size(250, 250);
}

void draw() {
  drawCircleGrid();
}

void drawCircleGrid() {
  for (float i = dia/2; i < width; i += dia) {
    for (float k = dia/2; k < width; k += dia) {
      fill(getBrightness(mouseX, mouseY, i, k));
      circle(i, k, dia);
    }
  }
}

float getBrightness(float mouseXPos, float mouseYPos, float x, float y) {
  return maxBrightness - dist(mouseXPos, mouseYPos, x, y);
}

Consider the program below and state what will be printed onto the console

String text = "outside";

void setup() {
  say("hi");
}

void say(String text) {
  text = "inside";
  println(text);
}