AoC2022_Day15/main.cpp

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

using namespace olc;

struct Sensor{
    vi2d pos;
    int radius;
};

int main()
{
	std::ifstream file("input");
    std::vector<Sensor>sensors;
    while (file.good()){
        std::string line;
        std::getline(file,line);
        std::cout<<line<<std::endl;
        int prevMarker=0;
        int marker=line.find(' ',prevMarker);
        vi2d sensorPos={-999,-999};
        vi2d beaconPos={-999,-999};
        if (line.length()>0){
            while (prevMarker!=std::string::npos){
                std::string word=line.substr(prevMarker,marker-prevMarker);
                prevMarker=marker;
                marker=line.find(' ',prevMarker+1);
                if (word[1]=='x'){
                    if (sensorPos.x==-999){
                        sensorPos.x=std::atoi(word.substr(word.find('=')+1,word.find(',')-word.find('=')-1).c_str());
                        std::cout<<"Sensor X: "<<sensorPos.x<<std::endl;
                    } else {
                        beaconPos.x=std::atoi(word.substr(word.find('=')+1,word.find(',')-word.find('=')-1).c_str());
                        std::cout<<"Beacon X: "<<beaconPos.x<<std::endl;
                    }
                } else
                if (word[1]=='y'){
                    if (sensorPos.y==-999){
                        sensorPos.y=std::atoi(word.substr(word.find('=')+1,word.find(',')-word.find('=')-1).c_str());
                        std::cout<<"Sensor Y: "<<sensorPos.y<<std::endl;
                    } else {
                        beaconPos.y=std::atoi(word.substr(word.find('=')+1,word.find(',')-word.find('=')-1).c_str());
                        std::cout<<"Beacon Y: "<<beaconPos.y<<std::endl;
                    }
                }
            }
            sensors.push_back({sensorPos,std::abs(beaconPos.x-sensorPos.x)+std::abs(beaconPos.y-sensorPos.y)});
            std::cout<<"Sensor -> Beacon Radius: "<<sensors[sensors.size()-1].radius<<std::endl;
            std::cout<<std::endl;
        }
    }
    int targetY=2000000;
    int sum=0;
    std::vector<std::pair<int,int>>ranges;
    for (Sensor s:sensors){
        int distance=std::abs(s.pos.y-targetY);
        if (distance<s.radius){
            //In range.
            std::cout<<"Sensor "<<s.pos<<" in range of Y "<<targetY<<" Radius: "<<s.radius<<std::endl;
            int rangeSize=s.radius*2-distance*2+1;
            std::cout<<"Leaves a range of "<<rangeSize<<std::endl;
            int minX=(s.pos.x-rangeSize/2);
            int maxX=(s.pos.x+rangeSize/2);
            std::cout<<"Range is from "<<minX<<" ~ "<<maxX<<std::endl;
            for (int i=0;i<ranges.size();i++){
                if (ranges[i].first<=minX&&ranges[i].second>=maxX){
                    maxX=minX-1;
                    break;
                }
                if (ranges[i].first>minX&&ranges[i].second<maxX){
                    sum-=ranges[i].second-ranges[i].first+1;
                    std::cout<<"  --> Removed Range "<<ranges[i].first<<" ~ "<<ranges[i].second<<std::endl;
                    ranges.erase(ranges.begin()+i--);
                }
                if (ranges[i].first<=maxX&&ranges[i].second>=maxX){
                    maxX=ranges[i].first-1;
                }
                if (ranges[i].first<=minX&&ranges[i].second>=minX){
                    minX=ranges[i].second+1;
                }
            }
            if (maxX>=minX){
                std::cout<<"  --> Range is truncated to "<<minX<<" ~ "<<maxX<<std::endl;
                sum+=maxX-minX+1;
                ranges.push_back({minX,maxX});
            }
        }
    }
    std::cout<<"Sum: "<<sum-1<<std::endl;

	return 0;
}