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class Solution {
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  public int robotSim(int[] commands, int[][] obstacles) {
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    int dir = 0; // states 0north-1east-2south-3west
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    int farthestSofar = 0;
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    int xloc = 0;
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    int yloc = 0;
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    Set<String> set = new HashSet<>();
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    for (int[] obs : obstacles) {
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      set.add(obs[0] + "," + obs[1]);
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    }
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    int steps;
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    for (int i : commands) {
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      if (i == -1) { // turn right 90
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        dir++;
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      } else if (i == -2) { // turn left 90
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        dir--;
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      } else { // move forward value of i baring no obsticals
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        dir = dir % 4;
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        if (dir == -1) {
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          dir = 3;
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        } else if (dir == -3) {
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          dir = 1;
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        } else if (dir == -2) {
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          dir = 2;
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        }
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        // dir %4 = -1 -> 3
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        // dir %4 = -2 -> 2
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        // dir %4 = -3 -> 1
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        if (dir == 0) {
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          steps = 0;
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          while (steps < i && !set.contains((xloc) + "," + (yloc + 1))) {
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            yloc++;
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            steps++;
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          }
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        } else if (dir == 1) {
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          steps = 0;
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          while (steps < i && !set.contains((xloc + 1) + "," + (yloc))) {
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            xloc++;
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            steps++;
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          }
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        } else if (dir == 2) {
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          steps = 0;
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          while (steps < i && !set.contains((xloc) + "," + (yloc - 1))) {
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            yloc--;
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            steps++;
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          }
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        } else { // case dir == 3
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          steps = 0;
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          while (steps < i && !set.contains((xloc - 1) + "," + (yloc))) {
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            xloc--;
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            steps++;
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          }
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        }
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      }
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      farthestSofar = Math.max(farthestSofar, xloc * xloc + yloc * yloc);
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    }
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    return farthestSofar;
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  }
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}