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package g1401_1500.s1496_path_crossing;
// #Easy #String #Hash_Table #2022_03_23_Time_1_ms_(97.41%)_Space_42.9_MB_(31.41%)
import java.util.ArrayDeque;
import java.util.Deque;
import java.util.Objects;
public class Solution {
public boolean isPathCrossing(String path) {
Deque visited = new ArrayDeque<>();
visited.add(new Coord(0, 0));
for (char c : path.toCharArray()) {
Coord last = visited.peek();
if (c == 'N') {
Coord nextStep = new Coord(last.x, last.y + 1);
if (visited.contains(nextStep)) {
return true;
}
visited.add(nextStep);
} else if (c == 'S') {
Coord nextStep = new Coord(last.x, last.y - 1);
if (visited.contains(nextStep)) {
return true;
}
visited.add(nextStep);
} else if (c == 'E') {
Coord nextStep = new Coord(last.x - 1, last.y);
if (visited.contains(nextStep)) {
return true;
}
visited.add(nextStep);
} else if (c == 'W') {
Coord nextStep = new Coord(last.x + 1, last.y);
if (visited.contains(nextStep)) {
return true;
}
visited.add(nextStep);
}
}
return false;
}
private static class Coord {
int x;
int y;
public Coord(int x, int y) {
this.x = x;
this.y = y;
}
@Override
public boolean equals(Object o) {
if (this == o) {
return true;
}
if (o == null || getClass() != o.getClass()) {
return false;
}
Coord coord = (Coord) o;
return x == coord.x && y == coord.y;
}
@Override
public int hashCode() {
return Objects.hash(x, y);
}
}
}