Leetcode#54 Spiral Matrix

原题地址

简单模拟，用t,b,l,r分别表示当前的上下左右四个边界，然后遍历即可

代码：

vector<int> spiralOrder(vector<vector<int> > &matrix) {
  if (matrix.empty() || matrix[0].empty()) return vector<int>();

  vector<int> path;
  int m = matrix.size();
  int n = matrix[0].size();
  int t = 0;
  int b = m - 1;
  int l = 0;
  int r = n - 1;
  int i = 0;
  int j = 0;

  while (t <= b && l <= r) {
    while (t <= b && l <= r && j <= r) path.push_back(matrix[i][j++]);
    i++;
    j--;
    t++;
    while (t <= b && l <= r && i <= b) path.push_back(matrix[i++][j]);
    i--;
    j--;
    r--;
    while (t <= b && l <= r && j >= l) path.push_back(matrix[i][j--]);
    i--;
    j++;
    b--;
    while (t <= b && l <= r && i >= t) path.push_back(matrix[i--][j]);
    i++;
    j++;
    l++;
  }

  return path;
}