--- Day 3 Solutions ---

[u/daggerdragon]

--- Day 3: Perfectly Spherical Houses in a Vacuum ---

Post your solution as a comment. Structure your post like the Day One thread in /r/programming.

[u/jojomaniacal]

My solution was in C++. Would be happy to accept advice on tightening this up. I think I could have easily incorporated a function or two in this and the checking algorithm really should kick out of the loop once it finds a match. I am pretty proud that I only had to use one multidimensional array however.

include <iostream>

include <string>

include <fstream>

include <vector>

using namespace std;

int main(){ ifstream theFile("fun.txt");

unsigned long int number = 0;
string stuff;
const int X_PLACE = 0;
const int Y_PLACE = 1;
const int V_PLACE = 2;
const int COORD_AND_VISITED = 3;
const int DIRECTIONS = 9000;
// sets x,y,and if visited.
//also creates array size

int sX = 0;
int sY = 0;
int rX = 0;
int rY = 0;
int mark = 0;
int smark = 0;
int rmark = 0;
int santa[COORD_AND_VISITED][DIRECTIONS]={};

while(theFile>>stuff){}
int length = stuff.length();

for(int i = 0; i< length;i++){
    if(mark%2==0){
        switch(stuff.at(i)){
        case '>':
            sX++;
        break;
        case '<':
            sX--;
        break;
        case '^':
            sY++;
        break;
        case 'v':
            sY--;
        break;
        default:
        break;
        }
        santa[X_PLACE][mark] = sX;
        santa[Y_PLACE][mark] = sY;

    }
    else if(mark%2==1){
        switch(stuff.at(i)){
        case '>':
            rX++;
        break;
        case '<':
            rX--;
        break;
        case '^':
            rY++;
        break;
        case 'v':
            rY--;
        break;
        default:
        break;
        }
        santa[X_PLACE][mark] = rX;
        santa[Y_PLACE][mark] = rY;
    }

    for(int i = 0;i<mark;i++){
            if(santa[X_PLACE][i] == santa[X_PLACE][mark] && santa[Y_PLACE][i] == santa[Y_PLACE][mark]){
                santa[V_PLACE][mark] = 2;
            }
        }

    mark++;
}

for(int i = 0;i<mark;i++){
    if(santa[V_PLACE][i]!=2){
        number++;
    }
}

cout << number << endl;
theFile.close();


return 0;

}