Added solution to problem 26

src/Problems.rs

@@ -48,3 +48,4 @@ pub mod Problem22;
 pub mod Problem23;
 pub mod Problem24;
 pub mod Problem25;
+pub mod Problem26;

src/Problems/Problem26.rs

@@ -0,0 +1,92 @@
+//ProjectEulerRust/src/Problems/Problems26.rs
+//Matthew Ellison
+// Created: 06-17-20
+//Modified: 06-17-20
+//Find the value of d < 1000 for which 1/d contains the longest recurring cycle in its decimal fraction part.
+//Unless otherwise listed all non-standard includes are my own creation and available from https://bibucket.org/Mattrixwv/RustClasses
+/*
+	Copyright (C) 2020  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/>.
+*/
+
+
+extern crate myClasses;
+use crate::Problems::Answer::Answer;
+
+pub fn getDescription() -> String{
+	"Find the value of d < 1000 for which 1/d contains the longest recurring cycle in its decimal fraction part.".to_string()
+}
+
+pub fn solve() -> Answer{
+	let TOP_NUM = 999;
+	//The length of the longest cycle
+	let mut longestCycle = 0;
+	//The starting denominator of the longest cycle
+	let mut longestNumber = 0;
+
+	//Start the timer
+	let mut timer = myClasses::Stopwatch::Stopwatch::new();
+	timer.start();
+
+	//Start with 1/2 and find out how long the longest cycle is by checking the remainders
+	//Loop through every number from 2-999 and use it for the denominator
+	for denominator in 2..=TOP_NUM{
+		let mut denomList = Vec::<i64>::new();
+		let mut endFound = false;	//Whether we have found an end to the number (either a cycle or a 0 for remainder)
+		let mut cycleFound = false;	//Whether a cycle was detected
+		let mut numerator = 1;	//The numerator that will be divided. Always starts at 1
+		while(!endFound){
+			//Get the remainder after the division
+			let remainder = numerator % denominator;
+			//Check if the remainder is 0
+			//If it is set the flag
+			if(remainder == 0){
+				endFound = true;
+			}
+			//Check if the remainder is in the list
+			//If it is in the list, set the appropriate flags
+			else if(denomList.contains(&remainder)){
+				endFound = true;
+				cycleFound = true;
+			}
+			//Else add it to the list
+			else{
+				denomList.push(remainder);
+			}
+			//Multiply the remainder by 10 to continue finding the next remainder
+			numerator = remainder * 10;
+		}
+		//If a cycle was found check the size of the list against the largest cycle
+		if(cycleFound){
+			//If it is larger than the largest, set it as the new largest
+			if(denomList.len() > longestCycle){
+				longestCycle = denomList.len();
+				longestNumber = denominator;
+			}
+		}
+	}
+
+	//Stop the timer
+	timer.stop();
+
+	//Return the results
+	return Answer::new(format!("The longest cycle is {} digits long\nIt started with the number {}", longestCycle, longestNumber), timer.getString());
+}
+
+/* Results:
+The longest cycle is 982 digits long
+It started with the number 983
+It took 6.518 milliseconds to solve this problem
+*/

src/main.rs

@@ -33,9 +33,9 @@ mod Problems;
 #[derive(PartialEq)]
 enum Selections{EMPTY, SOLVE, DESCRIPTION, LIST, EXIT, SIZE}
 
-static problemNumbers: [u32; 26] = [ 0,  1,  2,  3,  4,  5,  6,  7,  8,  9,
+static problemNumbers: [u32; 27] = [ 0,  1,  2,  3,  4,  5,  6,  7,  8,  9,
 									10, 11, 12, 13, 14, 15, 16, 17, 18, 19,
-									20, 21, 22, 23, 24, 25];
+									20, 21, 22, 23, 24, 25, 26];
 
 fn main(){
 	let mut selection = Selections::EMPTY;
@@ -232,6 +232,10 @@ fn solveProblem(problemNumber: u32){
 		println!("{}", Problems::Problem25::getDescription());
 		println!("{}", Problems::Problem25::solve());
 	}
+	else if(problemNumber == 26){
+		println!("{}", Problems::Problem26::getDescription());
+		println!("{}", Problems::Problem26::solve());
+	}
 }
 fn descriptionMenu(){
 	//Give some extra space to print the description
@@ -332,6 +336,9 @@ fn printDescription(problemNumber: u32){
 	else if(problemNumber == 25){
 		println!("{}", Problems::Problem25::getDescription());
 	}
+	else if(problemNumber == 26){
+		println!("{}", Problems::Problem26::getDescription());
+	}
 }
 fn getProblemNumber() -> u32{
 	println!("Enter a problem number: ");