Leetcode4 Spiral Matrix II

1、题目描述
Given an integer n, generate a square matrix filled with elements from 1 to n2 in spiral order.

For example,
Given n = 3,

You should return the following matrix:
[
[ 1, 2, 3 ],
[ 8, 9, 4 ],
[ 7, 6, 5 ]
]
2、解题思路
将矩阵赋值分为四部分，向右、向下、向左、向上四个方向上的循环赋值
3、代码

#include<iostream>using namespace std;int main(){    int n;    cout<<"please input the n: ";     cin>>n;    int matrix[n][n];    int i=0,j=0,x=n,y=n,left=n*n,temp=1;        while(left--){        //toword rigt        for(int k=i;k<x;++k){            matrix[j][k]=temp;            ++temp;        }        ++j;        //toward down         for(int k=j;k<y;++k){            matrix[k][x-1]=temp;            ++temp;        }        --x;        //toward left        for(int k=x-1;k>=i;--k){            matrix[y-1][k]=temp;            ++temp;        }        --y;        //toward up        for(int k=y-1;k>=j;--k){            matrix[k][i]=temp;            ++temp;        }        ++i;    }    //output     for(int k1=0;k1<n;++k1){        for(int k2=0;k2<n;++k2){            cout<<matrix[k1][k2]<<"\t";        }        cout<<endl;    }    return 0;}

4、结果图