[LeetCode]59.Spiral Matrix II

【题目】

Given an integern, generate a square matrix filled with elements from 1 ton2in spiral order.

For example,Givenn=3,

You should return the following matrix:[ [ 1, 2, 3 ], [ 8, 9, 4 ], [ 7, 6, 5 ]]【分析】

模拟

【代码】 /**————————————* 日期：2015-02-04* 作者：SJF0115* 题目: 59.Spiral Matrix II* 网址：https://oj.leetcode.com/problems/spiral-matrix-ii/* 结果：AC* 来源：LeetCode* 博客：—————————————**/#include <iostream>#include <vector>#include <algorithm>using namespace std;class Solution {public:vector<vector<int> > generateMatrix(int n) {vector<vector<int> > matrix(n,vector<int>(n,0));if(n <= 0){return matrix;}//ifint count = n * n;int index = 1;int x = 0,y = -1;while(index <= count){// right++y;while(y < n && matrix[x][y] == 0){matrix[x][y++] = index;++index;}//while–y;// down++x;while(x < n && matrix[x][y] == 0){matrix[x++][y] = index;++index;}//while–x;// left–y;while(y >= 0 && matrix[x][y] == 0){matrix[x][y–] = index;++index;}//while++y;// up–x;while(x >= 0 && matrix[x][y] == 0){matrix[x–][y] = index;++index;}//while++x;}//whilereturn matrix;}};int main(){Solution s;int n = 5;vector<vector<int> > matrix = s.generateMatrix(n);// 输出for(int i = 0;i < n;++i){for(int j = 0;j < n;++j){cout<<matrix[i][j]<<" ";}//forcout<<endl;}//forreturn 0;}

【代码二】

/**————————————* 日期：2015-02-05* 作者：SJF0115* 题目: 59.Spiral Matrix II* 网址：https://oj.leetcode.com/problems/spiral-matrix-ii/* 结果：AC* 来源：LeetCode* 博客：—————————————**/ class Solution {public:vector<vector<int> > generateMatrix(int n) {vector<vector<int> > matrix(n,vector<int>(n,0));if(n <= 0){return matrix;}//ifint count = n * n;int index = 1;int beginX = 0,endX = n – 1;int beginY = 0,endY = n – 1;while(index <= count){// rightfor(int i = beginY;i <= endY;++i){matrix[beginX][i] = index;++index;}//for++beginX;// downfor(int i = beginX;i <= endX;++i){matrix[i][endY] = index;++index;}//for–endY;// leftfor(int i = endY;i >= beginY;–i){matrix[endX][i] = index;++index;}//for–endX;// upfor(int i = endX;i >= beginX;–i){matrix[i][beginY] = index;++index;}++beginY;}//whilereturn matrix;}};

，一遍一遍的……你突然明白自己还活着，