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Two Letter Combinations

Nov 18, 2022AustinLeath
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Egg Problem Template

Jul 10, 2023LeifMessinger

0 likes • 4 views

#include <iostream>
#include <vector>
#include <limits>
#define DEBUG_TRIAL false
class Trial{
public:
const size_t HEIGHT;
std::string record;
//Breaking height is the index of the floor, so 0 is the bottom floor, height-1 is the top floor.
//Eggs is the eggs remaining.
//Start is the bottom floor.
//End is one above the top floor.
const size_t BREAKING_HEIGHT;
size_t eggs;
size_t start;
size_t end;
size_t floorsLeft(){
return (end-start);
}
size_t middle(){
return start + (floorsLeft()/2UL);
}
size_t drops = 0;
Trial(const size_t BREAKING_HEIGHT, size_t eggs, size_t start, size_t end): BREAKING_HEIGHT(BREAKING_HEIGHT), eggs(eggs), start(start), end(end), HEIGHT(end), record(end, '_'){
record[BREAKING_HEIGHT] = 'B'; //Marking the breaking point
}
bool foundAnswer(){
return ((record[0] == 'X') || (record.find("OX")!=std::string::npos));
}
//returns true if the egg broke.
//height is the index of the floor, so 0 is the bottom floor, height-1 is the top floor.
bool drop(size_t height){
#if DEBUG_TRIAL
std::cout << "Start: " << start << ". End: " << end << ". Floors Left: " << floorsLeft() << ". Middle Index: " << middle() << std::endl;
#endif
drops++;
bool cracked = height >= BREAKING_HEIGHT;
if(cracked) --eggs;
//Update the record
record[height] = (height >= BREAKING_HEIGHT)? 'X' : 'O';
#if DEBUG_TRIAL
//Print the record
std::cout << record << std::endl;
#endif
return cracked;
}
size_t nowWhat(){
if(foundAnswer()){
return drops;
}else if(eggs <= 0){ //Ran out of eggs
throw "Algorithm failed! No more eggs!";
return 1UL;
}else if(eggs > 1){
return wrecklessSearch();
}else{
return safeSearch();
}
}
size_t safeSearch(){
if(drop(start)){
--end;
}else{
++start;
}
return nowWhat();
}
size_t wrecklessSearch(){
//If the egg breaks
if(drop(middle())){
end -= (floorsLeft()/2UL);
}else{ //egg doesn't crack
start += (floorsLeft()/2UL);
}
return nowWhat();
}
//returns the amount of drops needed to find the answer
size_t search(){
return nowWhat();
}
};
//Height is the height of the building in floors.
//Breaking height is the index of the floor, so 0 is the bottom floor, height-1 is the top floor.
//Eggs is the eggs given.
//returns the amount of drops needed to find the answer
size_t search(const size_t height, const size_t BREAKING_HEIGHT, size_t eggs){
Trial trial(BREAKING_HEIGHT, eggs, 0, height);
return trial.search();
}
class TrialStats {
public:
size_t min = std::numeric_limits<size_t>::max();
size_t max = 0;
double mean = -1.0;
void printStats(){
// Print the results
std::cout << "Minimum drops: " << min << std::endl;
std::cout << "Maximum drops: " << max << std::endl;
std::cout << "Mean drops: " << mean << std::endl;
}
};
//Benchmarks all the possible breaking points of a single building height with a number of eggs.
TrialStats trial(const size_t HEIGHT, const size_t eggs){
TrialStats stats;
int totaldrops = 0;
//Test every possible breaking point
//Breaking height is the index of the floor, so 0 is the bottom floor, height-1 is the top floor.
for (int breakingHeight = 0; breakingHeight < HEIGHT; ++breakingHeight) {
size_t drops = search(HEIGHT, breakingHeight, eggs);
stats.min = std::min(stats.min, drops);
stats.max = std::max(stats.max, drops);
totaldrops += drops;
}
// Calculate the mean number of drops
stats.mean = static_cast<double>(totaldrops) / HEIGHT;
return stats;
}
//Benchmarks a single building height from 1 egg to MAX_EGGS
void testTower(const size_t height, const size_t MAX_EGGS){
//Drop every amount of eggs that you'd need.
for (int eggs = 1; eggs <= MAX_EGGS; ++eggs) {
std::cout << "Building height: " << height << ". Num eggs: " << eggs << std::endl;
TrialStats stats = trial(height, eggs);
stats.printStats();
std::cout << std::endl << std::endl;
}
}
//Benchmarks all buildings from 0 to MAX_HEIGHT
void benchmark(const size_t MAX_HEIGHT){
const size_t MAX_EGGS = 2;
//Test every building
for (size_t height = 1; height <= MAX_HEIGHT; ++height) {
testTower(height, std::min(height, MAX_EGGS));
}
}
int main() {
constexpr size_t MAX_HEIGHT = 36;
benchmark(MAX_HEIGHT);
return 0;
}

2D Array Chessboard Pattern

Nov 18, 2022AustinLeath

0 likes • 15 views

#include<iostream>
using namespace std;
const int rows = 8;
const int cols = 8;
char chessboard[rows][cols];
void setBoard(char chessboard[][cols]);
void printBoard(char chessboard[][cols]);
void setBoard(char chessboard[][cols]) {
for(int i = 0; i < rows; i++) {
for(int j = 0; j < cols; j++) {
if(i % 2 == 0 && j % 2 == 0) {
chessboard[i][j] = 'x';
} else {
if(i % 2 != 0 && j % 2 == 1) {
chessboard[i][j] = 'x';
} else {
chessboard[i][j] = '-';
}
}
}
}
return;
}
void printBoard(char chessboard[][cols]) {
for(int i = 0; i < rows; i++) {
for(int j = 0; j < cols; j++) {
cout << chessboard[i][j] << " ";
}
cout << endl;
}
return;
}
int main(int argc, char const *argv[])
{
setBoard(chessboard);
printBoard(chessboard);
return 0;
}

Heapify a vector

Nov 19, 2022CodeCatch

0 likes • 0 views

#include <iostream>
#include <vector>
using namespace std;
void swap(int *a, int *b)
{
int temp = *b;
*b = *a;
*a = temp;
}
void heapify(vector<int> &hT, int i)
{
int size = hT.size();
int largest = i;
int l = 2 * i + 1;
int r = 2 * i + 2;
if (l < size && hT[l] > hT[largest])
largest = l;
if (r < size && hT[r] > hT[largest])
largest = r;
if (largest != i)
{
swap(&hT[i], &hT[largest]);
heapify(hT, largest);
}
}
void insert(vector<int> &hT, int newNum)
{
int size = hT.size();
if (size == 0)
{
hT.push_back(newNum);
}
else
{
hT.push_back(newNum);
for (int i = size / 2 - 1; i >= 0; i--)
{
heapify(hT, i);
}
}
}
void deleteNode(vector<int> &hT, int num)
{
int size = hT.size();
int i;
for (i = 0; i < size; i++)
{
if (num == hT[i])
break;
}
swap(&hT[i], &hT[size - 1]);
hT.pop_back();
for (int i = size / 2 - 1; i >= 0; i--)
{
heapify(hT, i);
}
}
void printArray(vector<int> &hT)
{
for (int i = 0; i < hT.size(); ++i)
cout << hT[i] << " ";
cout << "\n";
}
int main()
{
vector<int> heapTree;
insert(heapTree, 3);
insert(heapTree, 4);
insert(heapTree, 9);
insert(heapTree, 5);
insert(heapTree, 2);
cout << "Max-Heap array: ";
printArray(heapTree);
deleteNode(heapTree, 4);
cout << "After deleting an element: ";
printArray(heapTree);
}

CSCE 1040 Lab 9

Nov 18, 2022AustinLeath

0 likes • 2 views

#include <iostream>
#include "PlaylistNode.h"
using namespace std;
void PrintMenu(string title);
int main() {
string plTitle;
cout << "Enter playlist's title:" << endl;
getline(cin, plTitle);
PrintMenu(plTitle);
return 0;
}
void PrintMenu(string title) {
Playlist list;
string id;
string sname;
string aname;
int length;
int oldPos;
int newPos;
char choice;
while(true) {
cout << endl << title << " PLAYLIST MENU" << endl;
cout << "a - Add song" << endl;
cout << "d - Remove song" << endl;
cout << "c - Change position of song" << endl;
cout << "s - Output songs by specific artist" << endl;
cout << "t - Output total time of playlist (in seconds)" << endl;
cout << "o - Output full playlist" << endl;
cout << "q - Quit" << endl << endl;
cout << "Choose an option:" << endl;
cin >> choice;
cin.ignore();
if (choice == 'q') {
exit(1);
}
else if (choice == 'a') {
cout << "\nADD SONG" << endl;
cout << "Enter song's unique ID: ";
cin >> id;
cin.ignore();
cout << "Enter song's name: ";
getline(cin,sname);
cout << "Enter artist's name: ";
getline(cin,aname);
cout << "Enter song's length (in seconds): ";
cin >> length;
list.AddSong(id, sname, aname, length);
}
else if (choice == 'd') {
cout << "\nREMOVE SONG" << endl;
cout << "Enter song's unique ID: ";
cin >> id;
list.RemoveSong(id);
}
else if (choice == 'c') {
cout << "\nCHANGE POSITION OF SONG" << endl;
cout << "Enter song's current position: ";
cin >> oldPos;
cout << "Enter new position for song: ";
cin >> newPos;
list.ChangePosition(oldPos, newPos);
}
else if (choice == 's') {
cout << "\nOUTPUT SONGS BY SPECIFIC ARTIST" << endl;
cout << "Enter artist's name: ";
getline(cin, aname);
list.SongsByArtist(aname);
}
else if (choice == 't') {
cout << "\nOUTPUT TOTAL TIME OF PLAYLIST (IN SECONDS)" << endl;
cout << "Total time: " << list.TotalTime() << " seconds" << endl;
}
else if (choice == 'o') {
cout << endl << title << " - OUTPUT FULL PLAYLIST" << endl;
list.PrintList();
}
else {
cout << "Invalid menu choice! Please try again." << endl;
}
}
}

Get Coefficient

Nov 18, 2022AustinLeath

0 likes • 4 views

#include <iostream>
using namespace std;
/* Function: get_coeff
Parameters: double& coeff, int pos passed from bb_4ac
Return: type is void so no return, but does ask for user to input data that establishes what a b and c are.
*/
void get_coeff(double& coeff, int pos) {
char position;
if(pos == 1) {
position = 'a';
} else if(pos == 2) { //a simple system to determine what coefficient the program is asking for.
position = 'b';
} else {
position = 'c';
}
cout << "Enter the co-efficient " << position << ":"; //prompt to input coeff
coeff = 5; //input coeff
}
/* Function: bb_4ac
Parameters: no parameters passed from main, but 3 params established in function, double a, b, c.
Return: b * b - 4 * a * c
*/
double bb_4ac() {
double a, b, c; //coefficients of a quadratic equation
get_coeff(a, 1); // call function 1st time
get_coeff(b, 2); // call function 2nd time
get_coeff(c, 3); // call function 3rd time
return b * b - 4 * a * c; //return b * b - 4 * a * c
}
int main() {
cout << "Function to calculate the discriminant of the equation. . . " << endl;
double determinate = bb_4ac(); //assign double determinate to bb_4ac function
cout << "The discriminant for given values is: " << determinate << endl; //output the determinate!
}

Daily: Find missing array value

Dec 24, 2021aedrarian

3 likes • 21 views

/*
Good morning! Here's your coding interview problem for today.
This problem was asked by Stripe.
Given an array of integers, find the first missing positive integer in linear time and constant space. In other words, find the lowest positive integer that does not exist in the array. The array can contain duplicates and negative numbers as well.
For example, the input [3, 4, -1, 1] should give 2. The input [1, 2, 0] should give 3.
You can modify the input array in-place.
*/
#include <iostream>
using namespace std;
int calcMissing(int* input, int size)
{
int sum = 0;
int n = 1; //add one to account for missing value
for(int i = 0; i < size; i++)
{
if(input[i] > 0)
{
sum += input[i];
n++;
}
}
//If no numbers higher than 0, answer is 1
if(sum == 0)
return 1;
return (n*(n+1)/2) - sum; //Formula is expectedSum - actualSum
/* expectedSum = n*(n+1)/2, the formula for sum(1, n) */
}
int main()
{
cout << calcMissing(new int[4]{3, 4, -1, 1}, 4) << endl;
cout << calcMissing(new int[3]{1, 2, 0}, 3) << endl;
//No positive numbers
cout << calcMissing(new int[1]{0}, 1) << endl;
}