豌豆荚面试

wandoujia-1.md

打印mxn螺旋矩阵

	class Solution {      
	public:      
	    vector<int> spiralOrder(vector<vector<int> >& matrix) {      
	        vector<int> result;      
	        if (matrix.empty()) return result;      
	        ssize_t beginX = 0, endX = matrix[0].size() - 1;      
	        ssize_t beginY = 0, endY = matrix.size() - 1;      
	  
	        while (true) {      
	            // From left to right      
	            for (ssize_t i = beginX; i <= endX; ++i)      
	                result.push_back(matrix[beginY][i]);      
	            if (++beginY > endY) break;      
	  
	            // From top down      
	            for (ssize_t i = beginY; i <= endY; ++i)      
	                result.push_back(matrix[i][endX]);      
	            if (beginX > --endX) break;      
	  
	            // From right to left      
	            for (ssize_t i = endX; i >= beginX; --i)      
	                result.push_back(matrix[endY][i]);      
	            if (beginY > --endY) break;      
	  
	            // From bottom up      
	            for (ssize_t i = endY; i >= beginY; --i)      
	                result.push_back(matrix[i][beginX]);      
	            if (++beginX > endX) break;      
	        }      
	        return result;      
	    }      
	};