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#include <cassert>
#include <iostream>
#include <vector>
using namespace std;
uint8_t shapes[5][4] = {
{
0,
0,
0,
0b00011110
},
{
0,
0b00001000,
0b00011100,
0b00001000,
},
{
0,
0b00000100,
0b00000100,
0b00011100,
},
{
0b00010000,
0b00010000,
0b00010000,
0b00010000,
},
{
0,
0,
0b00011000,
0b00011000,
},
};
uint8_t
signedShift(uint8_t a, int b) {
if (0 < b) return a >> b;
else return a << -b;
}
bool
collide(vector<uint8_t> const& map, int shapeID, int x, int y)
{
auto &shape = shapes[shapeID];
// y increasing upwards
for (int i = 0; i < 4; i++) {
uint8_t line = shape[3 - i];
if (signedShift(signedShift(line, x) & 0x7F, -x) != line) // wall coll
return true;
line = signedShift(line, x);
if (!(y + i < map.size())) continue;
if (line & map[y + i]) return true;
}
return false;
}
void
place(vector<uint8_t>& map, int shapeID, int x, int y)
{
auto &shape = shapes[shapeID];
for (int i = 0; i < 4; i++) {
uint8_t line = signedShift(shape[3 - i], x);
if (line == 0) break;
if (!(y + i < map.size())) map.push_back(0);
map[y + i] |= line;
}
}
void
vis(vector<uint8_t> const& map)
{
char l[9] = {0};
for (int i = map.size() - 1; 0 <= i; i--) {
for (int j = 0; j < 8; j++) {
l[7 - j] = (map[i] & (1 << j)) ? '#' : '.';
}
cout << l << endl;
}
cout << endl;
}
int
getWind(string const& s, int step)
{
char c = s[step % s.size()];
if (c == '<') return -1;
if (c == '>') return 1;
cout << s << endl;
throw "bad input";
}
int
main()
{
string input;
getline(cin, input);
int step = 0;
vector<uint8_t> map;
map.push_back(0x7F);
for (int i = 0; i < 2022; i++) {
int shape = i % 5;
int x = 0;
int y = map.size() + 3;
for (;;) {
int wind;
wind = getWind(input, step++);
if (!collide(map, shape, x + wind, y)) {
x += wind;
}
// cout << x << "," << y << endl;
if (collide(map, shape, x, y - 1)) {
break;
}
y--;
}
place(map, shape, x, y);
// vis(map);
}
cout << map.size() - 1 << endl;
}
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