Files
ProjectEulerJava/Problem8.java

88 lines
4.8 KiB
Java

//ProjectEuler/Java/Problem8.java
//Matthew Ellison
// Created: 03-28-19
//Modified: 03-01-19
//Find the thirteen adjacent digits in the 1000-digit number that have the greatest product. What is the value of this product?
/*
73167176531330624919225119674426574742355349194934
96983520312774506326239578318016984801869478851843
85861560789112949495459501737958331952853208805511
12540698747158523863050715693290963295227443043557
66896648950445244523161731856403098711121722383113
62229893423380308135336276614282806444486645238749
30358907296290491560440772390713810515859307960866
70172427121883998797908792274921901699720888093776
65727333001053367881220235421809751254540594752243
52584907711670556013604839586446706324415722155397
53697817977846174064955149290862569321978468622482
83972241375657056057490261407972968652414535100474
82166370484403199890008895243450658541227588666881
16427171479924442928230863465674813919123162824586
17866458359124566529476545682848912883142607690042
24219022671055626321111109370544217506941658960408
07198403850962455444362981230987879927244284909188
84580156166097919133875499200524063689912560717606
05886116467109405077541002256983155200055935729725
71636269561882670428252483600823257530420752963450
*/
//Unless otherwise listed all non-standard includes are my own creation and available from https://bibucket.org/Mattrixwv/JavaClasses
/*
Copyright (C) 2019 Matthew Ellison
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
import mattrixwv.Stopwatch;
public class Problem8{
private static final String NUMBER = "7316717653133062491922511967442657474235534919493496983520312774506326239578318016984801869478851843858615607891129494954595017379583319528532088055111254069874715852386305071569329096329522744304355766896648950445244523161731856403098711121722383113622298934233803081353362766142828064444866452387493035890729629049156044077239071381051585930796086670172427121883998797908792274921901699720888093776657273330010533678812202354218097512545405947522435258490771167055601360483958644670632441572215539753697817977846174064955149290862569321978468622482839722413756570560574902614079729686524145351004748216637048440319989000889524345065854122758866688116427171479924442928230863465674813919123162824586178664583591245665294765456828489128831426076900422421902267105562632111110937054421750694165896040807198403850962455444362981230987879927244284909188845801561660979191338754992005240636899125607176060588611646710940507754100225698315520005593572972571636269561882670428252483600823257530420752963450";
public static void main(String[] argv){
Stopwatch timer = new Stopwatch();
//Setup the variables
String maxNums = new String(); //Holds the string of the largest product
Long maxProduct = 0L; //Holds the largest product of 13 numbers
//Start the timer
timer.start();
//Cycle through the string of numbers looking for the maximum product
for(Integer cnt = 12;cnt < NUMBER.length();++cnt){
Long currentProduct = Long.parseLong(NUMBER.substring(cnt - 12, cnt - 11)) * Long.parseLong(NUMBER.substring(cnt - 11, cnt - 10)) * Long.parseLong(NUMBER.substring(cnt - 10, cnt - 9)) * Long.parseLong(NUMBER.substring(cnt - 9, cnt - 8)) * Long.parseLong(NUMBER.substring(cnt - 8, cnt - 7)) * Long.parseLong(NUMBER.substring(cnt - 7, cnt - 6)) * Long.parseLong(NUMBER.substring(cnt - 6, cnt - 5)) * Long.parseLong(NUMBER.substring(cnt - 5, cnt - 4)) * Long.parseLong(NUMBER.substring(cnt - 4, cnt - 3)) * Long.parseLong(NUMBER.substring(cnt - 3, cnt - 2)) * Long.parseLong(NUMBER.substring(cnt - 2, cnt - 1)) * Long.parseLong(NUMBER.substring(cnt - 1, cnt)) * Long.parseLong(NUMBER.substring(cnt, cnt + 1));
//Check if the product is greater than the current maximum
if(currentProduct > maxProduct){
maxNums = NUMBER.substring(cnt - 12, cnt + 1);
maxProduct = currentProduct;
}
}
//Stop the timer
timer.stop();
//Print the results
System.out.println("The greatest product is " + maxProduct.toString());
System.out.println("The numbers are " + maxNums);
System.out.println("It took " + timer.getStr() + " to run this algorithm");
}
}
/* Results:
The greatest product is 23514624000
The numbers are 5576689664895
It took 8.069 milliseconds to run this algorithm
*/