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// Path crossing
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// Leetcode
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class Solution {
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  public boolean isPathCrossing(String path) {
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    Set<String> visited = new HashSet<>();
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    int x = 0, y = 0;
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    visited.add(x + "," + y);
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    for (char c : path.toCharArray()) {
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      if (c == 'N') y++;
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      else if (c == 'S') y--;
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      else if (c == 'E') x++;
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      else x--;
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      if (visited.contains(x + "," + y)) return true;
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      visited.add(x + "," + y);
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    }
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    return false;
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  }
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}