Added solution to problem 19

src/Problems.rs

@@ -1,7 +1,7 @@
 //ProjectEulerRust/src/Problems.rs
 //Matthew Ellison
 // Created: 06-11-20
-//Modified: 06-15-20
+//Modified: 06-17-20
 //This file just forwards all the problem modules
 //Unless otherwise listed all non-standard includes are my own creation and available from https://bibucket.org/Mattrixwv/RustClasses
 /*
@@ -41,3 +41,4 @@ pub mod Problem15;
 pub mod Problem16;
 pub mod Problem17;
 pub mod Problem18;
+pub mod Problem19;

src/Problems/Problem19.rs

@@ -0,0 +1,197 @@
+//ProjectEulerRust/src/Problems/Problems19.rs
+//Matthew Ellison
+// Created: 06-17-20
+//Modified: 06-17-20
+//How many Sundays fell on the first of the month during the twentieth century (1 Jan 1901 to 31 Dec 2000)?
+/*
+You are given the following information, but you may prefer to do some research for yourself.
+1 Jan 1900 was a Monday.
+Thirty days has September,
+April, June and November.
+All the rest have thirty-one,
+Saving February alone,
+Which has twenty-eight, rain or shine.
+And on leap years, twenty-nine.
+A leap year occurs on any year evenly divisible by 4, but not on a century unless it is divisible by 400.
+*/
+//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{
+	"How many Sundays fell on the first of the month during the twentieth century (1 Jan 1901 to 31 Dec 2000)?".to_string()
+}
+
+#[allow(non_camel_case_types)]
+#[derive(PartialEq)]
+enum DAYS{SUNDAY, MONDAY, TUESDAY, WEDNESDAY, THRUSDAY, FRIDAY, SATURDAY, NUMBER_OF_DAYS, ERROR}
+
+pub fn solve() -> Answer{
+	//The first year we are going to test
+	let START_YEAR = 1901;
+	//The last year we are going to test
+	let END_YEAR = 2000;
+	//The total number of sundays
+	let mut totalSundays = 0;
+
+	//Start the timer
+	let mut timer = myClasses::Stopwatch::Stopwatch::new();
+	timer.start();
+
+	//Run for all years 1901-2000
+	for year in START_YEAR..=END_YEAR{
+		//Run for all months in the year
+		for month in 1..=12{
+			let day = getDay(month, 1, year);
+			if(day == DAYS::ERROR){
+				println!("There was an error with the day");
+			}
+			else if(day == DAYS::SUNDAY){
+				totalSundays += 1;
+			}
+		}
+	}
+
+	//Stop the timer
+	timer.stop();
+
+	//Return the results
+	return Answer::new(format!("There are {} Sundays that landed on the first of the months from {} to {}", totalSundays, START_YEAR, END_YEAR), timer.getString());
+}
+//Return the day of the week that the date you pass into it is on
+fn getDay(orgMonth: i32, orgDay: i32, orgYear: i32) -> DAYS{
+	let month = orgMonth;
+	let mut day = orgDay;
+	let year = orgYear;
+	//Make sure the number are within propper bounds
+	if((month < 1) || (month > 12) || (day < 1) || (day > 31) || (year < 1)){
+		return DAYS::ERROR;
+	}
+	let mut numDays = 0;
+	let mut currentYear = 1;
+	let mut currentMonth = 1;
+	let mut currentDay = DAYS::SATURDAY as i32;
+	day -= 1;
+
+	//Add the correct number of days for every year
+	while(currentYear < year){
+		if(isLeapYear(currentYear)){
+			numDays += 366;
+		}
+		else{
+			numDays += 365;
+		}
+		currentYear += 1;
+	}
+	//Add the correct number of days for every month
+	while(currentMonth < month){
+		//February
+		if(currentMonth == 2){
+			if(isLeapYear(currentYear)){
+				numDays += 29;
+			}
+			else{
+				numDays += 28;
+			}
+		}
+		//31 day months
+		else if((currentMonth == 1) || (currentMonth == 3) || (currentMonth == 5) || (currentMonth == 7) || (currentMonth == 8) || (currentMonth == 10) || (currentMonth == 12)){
+			numDays += 31;
+		}
+		else{
+			numDays += 30;
+		}
+		currentMonth += 1;
+	}
+	//Account for the weird year of 1752
+	if(year > 1752){
+		numDays -= 11;
+	}
+	else if(year == 1752){
+		if(month > 9){
+			numDays -= 11;
+		}
+		else if(month == 9){
+			if(day >= 14){
+				numDays -= 11;
+			}
+			//Days 3-13 were skipped that year
+			else if((day > 2) && (day < 14)){
+				println!("Hit 1752 error");
+				return DAYS::ERROR;
+			}
+		}
+	}
+	//Add the correct number of days for every day
+	numDays += day;
+
+	currentDay += numDays;
+	currentDay = currentDay % DAYS::NUMBER_OF_DAYS as i32;
+	if(currentDay == DAYS::SUNDAY as i32){
+		return DAYS::SUNDAY;
+	}
+	else if(currentDay == DAYS::MONDAY as i32){
+		return DAYS::MONDAY;
+	}
+	else if(currentDay == DAYS::TUESDAY as i32){
+		return DAYS::TUESDAY;
+	}
+	else if(currentDay == DAYS::WEDNESDAY as i32){
+		return DAYS::WEDNESDAY;
+	}
+	else if(currentDay == DAYS::THRUSDAY as i32){
+		return DAYS::THRUSDAY;
+	}
+	else if(currentDay == DAYS::FRIDAY as i32){
+		return DAYS::FRIDAY;
+	}
+	else if(currentDay == DAYS::SATURDAY as i32){
+		return DAYS::SATURDAY;
+	}
+	else{
+		println!("Hit default error");
+		return DAYS::ERROR;
+	}
+}
+//Returns true if the year passed to it is a leap year
+fn isLeapYear(year: i32) -> bool{
+	if(year < 1){
+		return false;
+	}
+	else if((year % 100) == 0){
+		//This rule only applies at and after 1800
+		if(year <= 1700){
+			return true;
+		}
+		else if((year % 400) == 0){
+			return true;
+		}
+	}
+	else if((year % 4) == 0){
+		return true;
+	}
+	return false;
+}
+
+/* Results:
+There are 171 Sundays that landed on the first of the months from 1901 to 2000
+It took 2.091 milliseconds to solve this problem
+*/

src/main.rs

@@ -33,8 +33,8 @@ mod Problems;
 #[derive(PartialEq)]
 enum Selections{EMPTY, SOLVE, DESCRIPTION, LIST, EXIT, SIZE}
 
-static problemNumbers: [u32; 19] = [ 0,  1,  2,  3,  4,  5,  6,  7,  8,  9,
-									10, 11, 12, 13, 14, 15, 16, 17, 18];
+static problemNumbers: [u32; 20] = [ 0,  1,  2,  3,  4,  5,  6,  7,  8,  9,
+									10, 11, 12, 13, 14, 15, 16, 17, 18, 19];
 
 fn main(){
 	let mut selection = Selections::EMPTY;
@@ -203,6 +203,10 @@ fn solveProblem(problemNumber: u32){
 		println!("{}", Problems::Problem18::getDescription());
 		println!("{}", Problems::Problem18::solve());
 	}
+	else if(problemNumber == 19){
+		println!("{}", Problems::Problem19::getDescription());
+		println!("{}", Problems::Problem19::solve());
+	}
 }
 fn descriptionMenu(){
 	//Give some extra space to print the description
@@ -282,6 +286,9 @@ fn printDescription(problemNumber: u32){
 	else if(problemNumber == 18){
 		println!("{}", Problems::Problem18::getDescription());
 	}
+	else if(problemNumber == 19){
+		println!("{}", Problems::Problem19::getDescription());
+	}
 }
 fn getProblemNumber() -> u32{
 	println!("Enter a problem number: ");