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class Solution {
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  public int[][] spiralMatrix(int m, int n, ListNode head) {
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    int[][] ans = new int[m][n];
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    for (int[] arr : ans) {
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      Arrays.fill(arr, -1);
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    }
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    int rowBegin = 0;
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    int rowEnd = m - 1;
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    int columnBegin = 0;
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    int columnEnd = n - 1;
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    ListNode cur = head;
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    while (rowBegin <= rowEnd && columnBegin <= columnEnd && cur != null) {
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      for (int i = columnBegin; i <= columnEnd && cur != null; i++) {
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        if (cur != null) {
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          ans[rowBegin][i] = cur.val;
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        }
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        cur = cur.next;
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      }
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      rowBegin++;
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      for (int i = rowBegin; i <= rowEnd && cur != null; i++) {
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        if (cur != null) {
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          ans[i][columnEnd] = cur.val;
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        }
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        cur = cur.next;
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      }
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      columnEnd--;
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      if (rowBegin <= rowEnd) {
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        for (int i = columnEnd; i >= columnBegin && cur != null; i--) {
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          if (cur != null) {
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            ans[rowEnd][i] = cur.val;
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          }
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          cur = cur.next;
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        }
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      }
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      rowEnd--;
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      if (columnBegin <= columnEnd) {
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        for (int i = rowEnd; i >= rowBegin && cur != null; i--) {
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          if (cur != null) {
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            ans[i][columnBegin] = cur.val;
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          }
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          cur = cur.next;
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        }
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      }
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      columnBegin++;
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    }
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    return ans;
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  }
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}