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Complete day 11

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Mattrixwv
2024-12-19 17:36:41 -05:00
parent c24cc156f3
commit a4dfc8f597
4 changed files with 207 additions and 1 deletions
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6
src/main/java/com/mattrixwv/adventOfCode24/ProblemSelector.java
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@@ -20,6 +20,8 @@ import com.mattrixwv.adventOfCode24.days.Problem18;
import com.mattrixwv.adventOfCode24.days.Problem19;
import com.mattrixwv.adventOfCode24.days.Problem2;
import com.mattrixwv.adventOfCode24.days.Problem20;
import com.mattrixwv.adventOfCode24.days.Problem21;
import com.mattrixwv.adventOfCode24.days.Problem22;
import com.mattrixwv.adventOfCode24.days.Problem3;
import com.mattrixwv.adventOfCode24.days.Problem4;
import com.mattrixwv.adventOfCode24.days.Problem5;
@@ -35,7 +37,7 @@ public class ProblemSelector{
protected static final List<Integer> PROBLEM_NUMBERS = List.of(
0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
10, 11, 12, 13, 14, 15, 16, 17, 18, 19,
20
20, 21, 22
);
@@ -68,6 +70,8 @@ public class ProblemSelector{
case 18 : day = new Problem18(); break;
case 19 : day = new Problem19(); break;
case 20 : day = new Problem20(); break;
case 21 : day = new Problem21(); break;
case 22 : day = new Problem22(); break;
default: throw new InvalidParameterException();
}
return day;

80
src/main/java/com/mattrixwv/adventOfCode24/days/Problem21.java Normal file
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@@ -0,0 +1,80 @@
package com.mattrixwv.adventOfCode24.days;
import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;
import com.mattrixwv.Stopwatch;
public class Problem21 extends Problem{
private static final String inputFileName = "days/Problem21.txt";
private static final int numIterations = 25;
private List<Long> stoneLine;
public Problem21(){
super();
description = "Find the number of stones after a given number of iterations.";
result = "Unresolved";
}
public String runSolution(){
Stopwatch timer = new Stopwatch();
timer.start();
//Read the file
stoneLine = new ArrayList<>();
try(Scanner scanner = new Scanner(this.getClass().getClassLoader().getResourceAsStream(inputFileName))){
scanner.useDelimiter(" ");
while(scanner.hasNext()){
String nextNum = scanner.next().strip();
if(!nextNum.isBlank()){
stoneLine.add(Long.parseLong(nextNum));
}
}
}
for(int cnt = 0;cnt < numIterations;++cnt){
stoneLine = performIteration(stoneLine);
}
//Save the result
timer.stop();
result = "There are " + stoneLine.size() + " stones after " + numIterations + " iterations.\nIt took " + timer.toString() + " to run this algorithm.";
return result;
}
private List<Long> performIteration(List<Long> stoneLine){
List<Long> newStoneLine = new ArrayList<>();
for(Long num : stoneLine){
if(num == 0){
newStoneLine.add(1L);
}
else if((num.toString().length() % 2) == 0){
String numString = num.toString();
String num1String = numString.substring(0, numString.length() / 2);
String num2String = numString.substring(numString.length() / 2);
newStoneLine.add(Long.parseLong(num1String));
newStoneLine.add(Long.parseLong(num2String));
}
else{
newStoneLine.add(num * 2024);
}
}
return newStoneLine;
}
}
/*
Find the number of stones after a given number of iterations.
There are 193269 stones after 25 iterations.
It took 47.751 milliseconds to run this algorithm.
*/

121
src/main/java/com/mattrixwv/adventOfCode24/days/Problem22.java Normal file
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@@ -0,0 +1,121 @@
package com.mattrixwv.adventOfCode24.days;
import java.util.HashMap;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Scanner;
import com.mattrixwv.Stopwatch;
public class Problem22 extends Problem{
private static final String inputFileName = "days/Problem21.txt";
private static final int numIterations = 75;
private Map<Long, Long> stoneLine;
public Problem22(){
super();
description = "Find the number of stones after a given number of iterations.";
result = "Unresolved";
}
public String runSolution(){
Stopwatch timer = new Stopwatch();
timer.start();
//Read the file
/* */
stoneLine = new HashMap<>();
try(Scanner scanner = new Scanner(this.getClass().getClassLoader().getResourceAsStream(inputFileName))){
scanner.useDelimiter(" ");
while(scanner.hasNext()){
String nextNum = scanner.next().strip();
if(!nextNum.isBlank()){
Long num = Long.parseLong(nextNum);
if(stoneLine.containsKey(num)){
stoneLine.put(num, stoneLine.get(num) + 1L);
}
else{
stoneLine.put(num, 1L);
}
}
}
}
/* */
/*
stoneLine = new HashMap<>();
stoneLine.put(125L, 1L);
stoneLine.put(17L, 1L);
/* */
for(int cnt = 0;cnt < numIterations;++cnt){
stoneLine = performIteration(stoneLine);
//System.out.println("New stone line = " + stoneLine);
//System.out.println("Iteration " + (cnt + 1));
}
Long sum = 0L;
for(Entry<Long, Long> entry : stoneLine.entrySet()){
sum += entry.getValue();
}
//Save the result
timer.stop();
result = "There are " + sum + " stones after " + numIterations + " iterations.\nIt took " + timer.toString() + " to run this algorithm.";
return result;
}
private Map<Long, Long> performIteration(Map<Long, Long> stoneLine){
Map<Long, Long> newStoneLine = new HashMap<>();
for(Entry<Long, Long> entry : stoneLine.entrySet()){
Long num = entry.getKey();
Long value = entry.getValue();
if(num == 0){
newStoneLine.put(1L, value);
}
else if((num.toString().length() % 2) == 0){
String numString = num.toString();
String num1String = numString.substring(0, numString.length() / 2);
String num2String = numString.substring(numString.length() / 2);
Long num1 = Long.parseLong(num1String);
Long num2 = Long.parseLong(num2String);
if(newStoneLine.containsKey(num1)){
newStoneLine.put(num1, newStoneLine.get(num1) + value);
}
else{
newStoneLine.put(num1, value);
}
if(newStoneLine.containsKey(num2)){
newStoneLine.put(num2, newStoneLine.get(num2) + value);
}
else{
newStoneLine.put(num2, value);
}
}
else{
Long newNum = num * 2024;
if(newStoneLine.containsKey(newNum)){
newStoneLine.put(newNum, newStoneLine.get(newNum) + value);
}
else{
newStoneLine.put(newNum, value);
}
}
}
return newStoneLine;
}
}
/*
Find the number of stones after a given number of iterations.
There are 228449040027793 stones after 75 iterations.
It took 69.644 milliseconds to run this algorithm.
*/

1
src/main/resources/days/Problem21.txt Normal file
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@@ -0,0 +1 @@
475449 2599064 213 0 2 65 5755 51149