Added solution to Day5-2

Day5-2.cpp

@@ -0,0 +1,146 @@
+//Fun/AdventCalendar2020/Day5-2.cpp
+//Matthew Ellison
+// Created: 12-05-20
+//Modified: 12-05-20
+//Find your seat id from the boarding passes
+
+
+#include <iostream>
+#include <fstream>
+#include <string>
+#include <vector>
+#include "Stopwatch.hpp"
+#include "Algorithms.hpp"
+
+
+struct boardingPass{
+	std::string passString;
+	int rowNumber;
+	int columnNumber;
+	int seatId;
+	void setPassString(std::string newPass){
+		int minRow = 0;
+		int maxRow = 127;
+		//Set the whole string
+		passString = newPass;
+		//Determine the row the seat is in
+		for(int cnt = 0;cnt < 7;++cnt){
+			char half = newPass[cnt];
+			//Keep the smaller half
+			if(half == 'F'){
+				maxRow = (minRow + maxRow) / 2;
+			}
+			//Keep the larger half
+			else if(half == 'B'){
+				minRow = ((minRow + maxRow) / 2) + 1;
+			}
+			else{
+				std::cout << "ERROR! half must == F or B" << std::endl;
+				exit(1);
+			}
+		}
+		if(newPass[6] == 'F'){
+			rowNumber = maxRow;
+		}
+		else{
+			rowNumber = minRow;
+		}
+		int minSeat = 0;
+		int maxSeat = 7;
+		//Determine the column the seat is in
+		for(int cnt = 7;cnt < 10;++cnt){
+			char half = newPass[cnt];
+			if(half == 'L'){
+				maxSeat = (minSeat + maxSeat) / 2;
+			}
+			else if(half == 'R'){
+				minSeat = ((minSeat + maxSeat) / 2) + 1;
+			}
+			else{
+				std::cout << "ERROR! half must == R or L" << std::endl;
+				exit(1);
+			}
+		}
+		if(newPass[9] == 'L'){
+			columnNumber = maxSeat;
+		}
+		else{
+			columnNumber = minSeat;
+		}
+		//Determine the seatId
+		seatId = (rowNumber * 8) + columnNumber;
+	}
+	//Compare according to seatId
+	bool operator>(boardingPass& pass2){
+		return seatId > pass2.seatId;
+	}
+	bool operator>=(boardingPass& pass2){
+		return seatId >= pass2.seatId;
+	}
+	bool operator<(boardingPass& pass2){
+		return seatId < pass2.seatId;
+	}
+	bool operator<=(boardingPass& pass2){
+		return seatId <= pass2.seatId;
+	}
+	bool operator==(boardingPass& pass2){
+		return seatId == pass2.seatId;
+	}
+};
+
+
+std::vector<boardingPass> importData(){
+	std::vector<boardingPass> boardingPasses;
+	std::ifstream inputFile("inputs/Day5.txt");	//Open the input file
+
+	//Go through every element in the file and set it in the vector
+	int cnt = 1;
+	while(!inputFile.eof()){
+		boardingPass pass;
+		std::string currentPass;
+		inputFile >> currentPass;
+		if(!currentPass.empty()){
+			pass.setPassString(currentPass);
+		}
+		++cnt;
+		boardingPasses.push_back(pass);
+	}
+
+	return boardingPasses;
+}
+
+
+int main(){
+	mee::Stopwatch timer;
+	std::vector<boardingPass> passes = importData();
+	int yourSeatId;
+
+	//Start the timer
+	timer.start();
+
+
+	//Sort the list of passes by seatId
+	std::sort(passes.begin(), passes.end());
+
+	//Go through every pass in the list (except the ends) and your seat id should be one where seats on both sides are +/-1 off of yours
+	for(int cnt = 1;cnt < (passes.size() - 1);++cnt){
+		if(passes[cnt - 1].seatId == (passes[cnt].seatId - 2)){
+			yourSeatId = passes[cnt].seatId - 1;
+			break;
+		}
+	}
+
+	//Stop the timer
+	timer.stop();
+
+	//Print the results
+	std::cout << "Your seatId = " << yourSeatId
+			<<"\nIt took " << timer.getStr() << " to finish this problem" << std::endl;
+
+	return 0;
+}
+
+/* Results:
+Your seatId = 612
+It took 0.000 nanoseconds to finish this problem
+*/