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#include <cstdio>
#include <unordered_set>
#include <iostream>
using namespace std;
int signum(int n) {
if (0 < n) return 1;
if (n < 0) return -1;
return 0;
}
struct Pos {
int x, y;
Pos add(Pos other) {
return Pos{this->x+other.x,this->y+other.y};
}
Pos sub(Pos other) {
return Pos{this->x-other.x,this->y-other.y};
}
bool touching(Pos other) {
return abs(this->x - other.x) <= 1
&& abs(this->y - other.y) <= 1;
}
Pos moveTowards(Pos other) {
Pos p = *this;
if (!touching(other)) {
p.x += signum(other.x - this->x);
p.y += signum(other.y - this->y);
}
return p;
}
bool operator==(Pos const& p) const noexcept
{
return x == p.x && y == p.y;
}
};
template<>
struct std::hash<Pos>
{
size_t operator()(Pos const& p) const noexcept
{
return std::hash<int>{}(p.x) ^ (std::hash<int>{}(p.x) << 1);
}
};
int main() {
char dir;
int steps;
Pos head{0,0}, tail{0,0};
unordered_set<Pos> visited;
while (scanf("%c %d ", &dir, &steps) == 2) {
Pos d;
switch (dir) {
case 'R': d = {1, 0}; break;
case 'L': d = {-1, 0}; break;
case 'U': d = {0, -1}; break;
case 'D': d = {0, 1}; break;
default: throw "bad input";
}
for (int i = 0; i < steps; i++) {
head = head.add(d);
tail = tail.moveTowards(head);
visited.insert(tail);
}
}
cout << visited.size() << endl;
}
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