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class Solution {
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  public int[] prisonAfterNDays(int[] cells, int N) {
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    if (N == 0) return cells;
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    int[][] mem = new int[14][8]; // Repeat pattern after day 14, so Day 1 and Day 15 is equal
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    mem[0][0] = 0;
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    mem[0][7] = 0;
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    for (int i = 1; i < 7; i++) { // calculating Day 1 and insert at 0th position in mem
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      if (cells[i - 1] == cells[i + 1]) mem[0][i] = 1;
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      else mem[0][i] = 0;
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    }
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    for (int j = 1;
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        j < 14;
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        j++) { // calculating Day 2 to 14 and inserting at position 1 to 13 in mem.
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      for (int i = 1; i < 7; i++) {
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        if (mem[j - 1][i - 1] == mem[j - 1][i + 1]) mem[j][i] = 1;
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        else mem[j][i] = 0;
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      }
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    }
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    return mem[(N - 1) % 14]; // return the day modulo 14
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  }
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}