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class Solution {
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 public:
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  // N--> left(-2):W, right(-1):E
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  // S--> left:E, right:W
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  // E--> left:N, right:S
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  // W--> left:S, right:N
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  vector<vector<int>> change = { // for direction change
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      {3, 2},
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      {2, 3},
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      {0, 1},
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      {1, 0}};
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  vector<vector<int>> sign = {
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      // signs for x and y coordinates movement
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      {0, 1},  // North
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      {0, -1}, // south
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      {1, 0},  // east
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      {-1, 0}  // west
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  };
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  int robotSim(vector<int> &commands, vector<vector<int>> &obstacles) {
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    set<vector<int>> s;
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    for (int i = 0; i < obstacles.size(); i++) {
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      s.insert(obstacles[i]);
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    }
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    int direction = 0;
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    int ans = 0;
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    int xi = 0, yi = 0;
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    for (int i = 0; i < commands.size(); i++) {
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      if (commands[i] <= 9 && commands[i] >= 1) {
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        int signx = sign[direction][0];
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        int signy = sign[direction][1];
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        while (commands[i]) {
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          xi += signx;
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          yi += signy;
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          if (s.count({xi, yi})) {
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            xi -= signx;
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            yi -= signy;
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            break;
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          }
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          commands[i]--;
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        }
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      } else {
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        direction = change[direction][commands[i] + 2];
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      }
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      ans = max(ans, xi * xi + yi * yi);
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    }
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    return ans;
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  }
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};