adventOfCode2024/2/puzzle2p2.cpp
2024-12-03 18:58:51 +13:00

98 lines
No EOL
3.2 KiB
C++

#include <stdio.h>
#include <list>
#include <iostream>
#include <fstream>
#include <string>
#include <vector>
#include <sstream>
using namespace std;
enum Direction {
UP,
DOWN,
UNSET
};
int main(){
string line;
int safeReports = 0;
stringstream wholeDoc;
ifstream puzzle("input.txt", ifstream::in);
while (getline(puzzle, line)) {
istringstream lineStream(line);
string numberString;
list<int> currentLevels;
while (getline(lineStream, numberString, ' ')) {
int number = stoi(numberString);
currentLevels.push_back(number);
}
int numOfLevelsInLine = currentLevels.size();
int numOfLevelsProcessed = 0;
auto curListIt = currentLevels.begin();
curListIt++; //point to second item in list
auto RevCurListIt = currentLevels.rbegin();
RevCurListIt++; //points to second to last item
enum Direction dir;
bool listDirty =false;
list<int>changeFromPrevLevel;
list<int>levelGoesUp;
list<int>levelGoDown;
list<int>levelStaysSame;
int totalChange=0;
changeFromPrevLevel.push_front(0);
auto frontIt = currentLevels.begin();
frontIt++;
auto backIt = currentLevels.begin();
for(int index = 1;frontIt!=currentLevels.end();index++){
int change = (*backIt)-(*frontIt);
totalChange+=change;
changeFromPrevLevel.push_back(change);
frontIt++;
backIt++;
if (change>0){
levelGoesUp.push_front(index);
} else if(change<0){
levelGoDown.push_front(index);
} else {
levelStaysSame.push_front(index);
}
}
float averageChange = totalChange/(currentLevels.size()-1);
//need to pull the first one to have something to compare to
int prevlevel = currentLevels.front();
currentLevels.pop_front();
numOfLevelsProcessed++;
if (prevlevel < currentLevels.front()){
dir = DOWN;
} else if (prevlevel > currentLevels.front()){
dir = UP;
} else {
currentLevels.clear();
}
for (int level = currentLevels.front(); !currentLevels.empty();level=currentLevels.front()){
if (abs(prevlevel-level)>3) {currentLevels.clear();break;}
if(prevlevel==level){ currentLevels.clear();break;}
if(dir==UP&&(prevlevel<currentLevels.front())) {currentLevels.clear();break;}
if(dir==DOWN&&(prevlevel>currentLevels.front())) {currentLevels.clear();break;}
prevlevel=currentLevels.front();
currentLevels.pop_front();
numOfLevelsProcessed++;
if(numOfLevelsProcessed==numOfLevelsInLine){
safeReports++;
}
}
}
cout << safeReports;
puzzle.close();
}