Files
contests/advent_of_code/2022/9/main.cpp

84 lines
2.3 KiB
C++

#include <bits/stdc++.h>
using namespace std;
using Coords = pair<int, int>;
void moveTail(const Coords& head, Coords& tail){
if(head.first - tail.first > 1){
tail.first++;
} else if(head.first - tail.first < -1){
tail.first--;
}
if(head.second - tail.second > 1){
tail.second++;
} else if(head.second - tail.second < -1){
tail.second--;
}
// if(abs(head.first - tail.first) > 1 || abs(head.second - tail.second) > 1){
// if(abs(head.first - tail.first) >= 1 && abs(head.second - tail.second) >= 1){
// if(head.first > tail.first && head.second > tail.second){
// tail.first++;
// tail.second++;
// } else if(head.first > tail.first && head.second < tail.second){
// tail.first++;
// tail.second--;
// } else if(head.first < tail.first && head.second > tail.second){
// tail.first--;
// tail.second++;
// } else{
// tail.first--;
// tail.second--;
// }
// } else if(abs(head.first - tail.first > 1)){
// if(head.first > tail.first){
// tail.first++;
// } else{
// tail.first--;
// }
// } else{
// if(head.second > tail.second){
// tail.second++;
// } else{
// tail.second--;
// }
// }
// }
}
int main(){
ifstream input_file("test.txt");
string line;
Coords head(0, 0), tail(0, 0);
set<Coords> visited_by_tail;
visited_by_tail.insert(tail);
while(getline(input_file, line)){
stringstream ss(line);
char direction;
int steps;
ss >> direction >> steps;
while(steps > 0){
if(direction == 'R'){
head.first++;
} else if(direction == 'L'){
head.first--;
} else if(direction == 'U'){
head.second++;
} else if(direction == 'D'){
head.second--;
}
moveTail(head, tail);
visited_by_tail.insert(tail);
steps--;
}
}
cout << "Number of positions visited by the tail: " << visited_by_tail.size() << endl;
return 0;
}