CodeHS AP CSP answers

====JS Control Stuctures 6.6.4-6.8.4====
==6.6.4==
function start(){
    var line = ["Sam", "Lisa", "Laurie", "Bob", "Ryan"];
    var line2 = ["Tony", "Lisa", "Laurie", "Karen"];
    if(line.indexOf("Bob") != -1) {println("Bob is in the first line.");}
    else{println("Bob is not in the first line.");}
    if(line2.indexOf("Bob") != -1) {println("Bob is in the second line.");}
    else{println("Bob is not in the second line.");}
    // Your code goes here
}
==6.7.4==
function start(){
    var line = ["Sam", "Lisa", "Laurie", "Bob", "Ryan"];
    // Your code goes here
    println(line[0] + ", " + line[1] + ", " + line[2] + ", " +line[3] + ", " +line[4]);
    line.remove("Sam");
    line.remove("Lisa");
    println(line[0] + ", " + line[1] + ", " + line[2]);
}
==6.8.4==
function start() {
    // Create your coin flip simulation here
    var i = 0;
    while(i < 100) {
        if(Randomizer.nextBoolean()) {println("Heads");}
        else {println("Tails");}
        i++;
    }
}
====Digital Information====
==7.3.7==
01001000
01100101
01101100
01101100
01101111
00101100
00100000
01001011
01100001
01110010
01100101
01101100
00100001
==7.4.5==
01010101 10101010 01010101 10101010 01010101 10101010 01010101 10101010
==7.4.6==
01110
01110
00000
01110
01110
00000
01110
01110
00000
01110
01110
00000
01110
01110
00000
01110
01110
00000
01110
01110
==7.4.7==
234234e2139649283764862497
==7.6.6==
FF0000
00FF00
0000FF
==7.6.7==
FF0000
00FF00
0000FF
FFFF00
==7.6.8==
FF0000
FF7700
FFFF00
00FF00
0000FF
FF00FF
==7.6.9==
79427549579475923759749579347593459294583458345843503450450ffdffff008508508f87f89d709f7d9f79427549579475923759749579347593459294583458345843503450450ffdffff008508508f87f89d709f7d9f79427549579475923759749579347593459294583458345843503450450ffdffff008508508f87f89d709f7d9f79427549579475923759749579347593459294583458345843503450450ffdffff008508508f87f89d709f7d9f79427549579475923759749579347593459294583458345843503450450ffdffff008508508f87f89d709f7d9f79427549579475923759749579347593459294583458345843503450450ffdffff008508508f87f89d709f7d9f79427549579475923759749579347593459294583458345843503450450ffdffff008508508f87f89d709f7d9f
==7.7.9==
// Constants for the image
var IMAGE_URL = "https://codehs.com/static/img/zebra.jpg";
var IMAGE_WIDTH = 350;
var IMAGE_HEIGHT = 250;
var IMAGE_X = getWidth() / 2 - IMAGE_WIDTH / 2;
var IMAGE_Y = getHeight() / 2 - IMAGE_HEIGHT / 2;

// Constants for the pixel array
var RED = 0;
var GREEN = 1;
var BLUE = 2;

// Constants for the pixel filter
var MAX_COLOR_VALUE = 255;

// We need to wait for the image to load before modifying it
var IMAGE_LOAD_WAIT_TIME = 50;

/*
 * Given a pixel array with 3 values [R, G, B]
 * Modifies the pixel array such that each value is inverted ie:
 * R = 255 - R
 * G = 255 - G
 * B = 255 - B
 * Returns the modified pixel array
 */
function invertPixel(pixel) {

    // WRITE THIS FUNCTION
    var red = pixel[0];
    var green = pixel[1];
    var blue = pixel[2];
    red = 255-red;
    blue = 255-blue;
    green = 255-green;
    var newPixel = [red,green,blue];
    return newPixel;

}

// Inverts the colors of each pixel in the WebImage image
function invert(image) {
    for(var x = 0; x < image.getWidth(); x++) {
        for (var y = 0; y < image.getHeight(); y++) {
            // Get the current pixel
            var pixel = image.getPixel(x, y);

            // Modify the current pixel
            pixel = invertPixel(pixel);

            // Update the image with the modified pixel
            image.setRed(x, y, pixel[RED]);
            image.setGreen(x, y, pixel[GREEN]);
            image.setBlue(x, y, pixel[BLUE]);
        }
    }
}

function start() {
    // Set up the image
    var image = new WebImage(IMAGE_URL);
    image.setSize(IMAGE_WIDTH, IMAGE_HEIGHT);
    image.setPosition(IMAGE_X, IMAGE_Y);

    // Add it to the canvas
    add(image);

    // Wait for it to load before applying the filter
    setTimeout(function(){
        invert(image);
    }, IMAGE_LOAD_WAIT_TIME);
}
==7.7.10==
// Constants for the image
var IMAGE_URL = "https://codehs.com/static/img/zebra.jpg";
var IMAGE_WIDTH = 350;
var IMAGE_HEIGHT = 250;
var IMAGE_X = getWidth() / 2 - IMAGE_WIDTH / 2;
var IMAGE_Y = getHeight() / 2 - IMAGE_HEIGHT / 2;

// We need to wait for the image to load before modifying it
var IMAGE_LOAD_WAIT_TIME = 50;

// Filter that sets the blue value of every pixel in the image to be 0
function removeBlue(image) {

    for (var x = 0; x < image.getWidth();x++) {
        for (var y = 0; y < image.getHeight();y++) {
            var pixel = getPixel(x,y);
            pixel[2] = 0;
            setPixel(x,y,pixel);
        }
    }
}

function start() {
    // Set up the image
    var image = new WebImage(IMAGE_URL);
    image.setSize(IMAGE_WIDTH, IMAGE_HEIGHT);
    image.setPosition(IMAGE_X, IMAGE_Y);

    // Add it to the canvas
    add(image);

    // Wait for it to load before applying the filter
    setTimeout(function(){
        removeBlue(image);
    }, IMAGE_LOAD_WAIT_TIME);
}
==7.7.11==
// Constants for the image
var IMAGE_URL = "https://codehs.com/static/img/about/goldengate.jpg";
var IMAGE_WIDTH = 350;
var IMAGE_HEIGHT = 250;
var IMAGE_X = getWidth() / 2 - IMAGE_WIDTH / 2;
var IMAGE_Y = getHeight() / 2 - IMAGE_HEIGHT / 2;

// Constants for the filter
var DARKENING_FACTOR = 25;
var MIN_PIXEL_VALUE = 0;

// Constants for pixel indices
var RED = 0;
var GREEN = 1;
var BLUE = 2;

// We need to wait for the image to load before modifying it
var IMAGE_LOAD_WAIT_TIME = 50;

// Filter that takes an image as a parameter
// and darkens the pixels in the left half of the image
function darkenFilter(image) {

    for (var x = 0; x < image.getWidth();x++) {
        for (var y = 0; y < image.getHeight();y++) {
            var pixel = image.getPixel(x,y);
            pixel[0] = pixel[0] - DARKENING_FACTOR;
            pixel[1] = pixel[1] - DARKENING_FACTOR;
            pixel[2] = pixel[2] - DARKENING_FACTOR;
            image.setPixel(x,y,pixel);
        }
    }

}

function start() {
    // Set up the image
    var image = new WebImage(IMAGE_URL);
    image.setSize(IMAGE_WIDTH, IMAGE_HEIGHT);
    image.setPosition(IMAGE_X, IMAGE_Y);

    // Add it to the canvas
    add(image);

    // Wait for it to load before applying the filter
    setTimeout(function(){
        darkenFilter(image);
    }, IMAGE_LOAD_WAIT_TIME);
}
==7.9.4==
0000000000001111110001011110100110110110011100111001110011100110110110010111101000111111000000000000
==7.10.8==
/*
 * Write a program that guesses every possible 4 digit passcode
 * combinations until the correct passcode is guessed.
 *
 * The passcode is randomly generated and stored in the variable
 * secretPasscode.
 *
 * Print out how many guesses it took to guess the correct passcode.
 */

    function start() {
    var secretPasscode = generateRandomPasscode();
    for (var guessInt = 0; guessInt < 1000; guessInt++) {
        let guess = pad(`${guessInt}`,4);
        if(guess === secretPasscode){
            println(`we just started counting, and found the passcode at ${guessInt} `);
            break;
        }
    }
}

function pad(str, length) {
    while (str.length < length) str = '0' + str;
    return str;
}


// Checks whether the given guess passcode is the correct passcode
function isCorrect(guessCode, correctCode) {
    return guessCode == correctCode;
}

// Generates a random 4 digit passcode and returns it as a String
function generateRandomPasscode() {
    var randomPasscode = "";

    for(var i = 0; i < 4; i++) {
        var randomDigit = Randomizer.nextInt(0, 9);
        randomPasscode += randomDigit;
    }

    return randomPasscode;
}
==7.13.2==
// DESCRIBE YOUR FILTER HERE IN THIS COMMENT!
function customFilter(image) {

    for (var x = 0; x < image.getWidth();x++) {
        for (var y = 0; y < image.getHeight();y++) {
            var pixel = getPixel(x,y);
            pixel[0] = 0;
            pixel[1] = Math.random();
            pixel[2] = 128;
            setPixel(x,y,pixel);
        }
    }
}


// WRITE ANY HELPER FUNCTIONS HERE

/*********************************************
 * You do not need to write any code below this line.
 * This is starter code that sets up the image on the screen
 * and calls your customFilter function.
 * Feel free to read this code and learn how it works!
 * Be careful though, if you modify this code the program may not
 * work correctly.
 *********************************************/

// Constants for the image
var IMAGE_URL = "https://codehs.com/static/img/zebra.jpg";
var IMAGE_WIDTH = 350;
var IMAGE_HEIGHT = 250;
var IMAGE_X = getWidth() / 2 - IMAGE_WIDTH / 2;
var IMAGE_Y = getHeight() / 2 - IMAGE_HEIGHT / 2;

// We need to wait for the image to load before modifying it
var IMAGE_LOAD_WAIT_TIME = 50;

function start() {
    // Set up the image
    var image = new WebImage(IMAGE_URL);
    image.setSize(IMAGE_WIDTH, IMAGE_HEIGHT);
    image.setPosition(IMAGE_X, IMAGE_Y);

    // Add it to the canvas
    add(image);

    // Wait for it to load before applying the filter
    setTimeout(function(){
        customFilter(image);
    }, IMAGE_LOAD_WAIT_TIME);
}