AoC2022_Day12/main.cpp

#define OLC_PGE_APPLICATION
#include "pixelGameEngine.h"
#include "olcutils.h"

using namespace olc;

std::vector<int> validPathStepCounts;
vi2d playerPos={0,0};
vi2d endingPos={0,0};
std::vector<std::vector<char>>grid;
int lowest=2468;

void step(char currentTile,vi2d pos,int xoffset,int yoffset,int stepCount,std::vector<std::vector<char>>visitedgrid,std::string currentPath){
    pos.x+=xoffset;
    pos.y+=yoffset;
    std::cout<<currentPath<<std::endl;
    if (currentTile=='S'){
        currentTile='a';
    }
    if (stepCount+abs(pos.x-endingPos.x)+abs(pos.y-endingPos.y)>lowest){
        //std::cout<<"Took too long..."<<std::endl;
        return;
    }
    if (pos.y<0||pos.x<0||pos.x>=visitedgrid[0].size()||pos.y>=visitedgrid.size()){
        //std::cout<<"Dead end reached in "<<stepCount<<" steps ("<<currentPath<<")"<<std::endl;
        return;
    }
    if (visitedgrid[pos.y][pos.x]!='0'&&(visitedgrid[pos.y][pos.x]!='E'&&visitedgrid[pos.y][pos.x]-currentTile<=1||visitedgrid[pos.y][pos.x]=='E'&&currentTile>='y')){
        currentPath+=visitedgrid[pos.y][pos.x];
        if (visitedgrid[pos.y][pos.x]=='E'){
            validPathStepCounts.push_back(++stepCount);
            if (stepCount<lowest){
                lowest=stepCount;
                std::cout<<"Valid path found in "<<stepCount<<" steps! ("<<currentPath<<")"<<std::endl;
            }
            return;
        }
        ++stepCount;
        char newTile=visitedgrid[pos.y][pos.x];
        visitedgrid[pos.y][pos.x]='0';
        if (pos.y+1<visitedgrid.size()&&visitedgrid[pos.y+1][pos.x]!='0'&&yoffset!=-1){
            //visitedgrid[pos.y+1][pos.x]='0';
            std::vector<std::vector<char>>newvisitedgrid=visitedgrid;
            step(newTile,pos,0,1,stepCount,newvisitedgrid,currentPath);
        }
        if (pos.y-1>=0&&visitedgrid[pos.y-1][pos.x]!='0'&&yoffset!=1){
            //visitedgrid[pos.y-1][pos.x]='0';
            std::vector<std::vector<char>>newvisitedgrid=visitedgrid;
            step(newTile,pos,0,-1,stepCount,newvisitedgrid,currentPath);
        }
        if (pos.x-1>=0&&visitedgrid[pos.y][pos.x-1]!='0'&&xoffset!=1){
            //visitedgrid[pos.y][pos.x-1]='0';
            std::vector<std::vector<char>>newvisitedgrid=visitedgrid;
            step(newTile,pos,-1,0,stepCount,newvisitedgrid,currentPath);
        }
        if (pos.x+1<visitedgrid[0].size()&&visitedgrid[pos.y][pos.x+1]!='0'&&xoffset!=-1){
            //visitedgrid[pos.y][pos.x+1]='0';
            std::vector<std::vector<char>>newvisitedgrid=visitedgrid;
            step(newTile,pos,1,0,stepCount,newvisitedgrid,currentPath);
        }
    }
}

int main()
{
	std::ifstream file("testinput2");
    while (file.good()){
        std::string line;
        std::getline(file,line);
        std::vector<char>row;
        if (line.length()>0){
            for (int x=0;x<line.length();x++){
                row.push_back(line[x]);
                if (line[x]=='S'){
                    playerPos={x,(int)grid.size()};
                }
                if (line[x]=='E'){
                    endingPos={x,(int)grid.size()};
                }
            }
            grid.push_back(row);
        }
    }

    std::cout<<"================"<<std::endl;
    for (int y=0;y<grid.size();y++){
        for (int x=0;x<grid[y].size();x++){
            std::cout<<grid[y][x];
        }
        std::cout<<std::endl;
    }
    std::cout<<"Player Pos: "<<playerPos<<std::endl;
    char newTile=grid[playerPos.y][playerPos.x];
    grid[playerPos.y][playerPos.x]='0';
    std::vector<std::vector<char>>visitedgrid=grid;
    std::vector<std::vector<char>>visitedgrid2=grid;
    std::vector<std::vector<char>>visitedgrid3=grid;
    std::vector<std::vector<char>>visitedgrid4=grid;
    std::cout<<"Part 1"<<std::endl;
    step(newTile,playerPos,1,0,0,visitedgrid,"S");
    std::cout<<"Part 2"<<std::endl;
    step(newTile,playerPos,-1,0,0,visitedgrid2,"S");
    std::cout<<"Part 3"<<std::endl;
    step(newTile,playerPos,0,1,0,visitedgrid3,"S");
    std::cout<<"Part 4"<<std::endl;
    step(newTile,playerPos,0,-1,0,visitedgrid4,"S");
    std::sort(validPathStepCounts.begin(),validPathStepCounts.end());
    for (int i=0;i<validPathStepCounts.size();i++){
        std::cout<<validPathStepCounts[i]<<std::endl;
    }
    std::cout<<"Best: "<<validPathStepCounts[0]<<std::endl;

	return 0;
}