1105. Spiral Matrix (25)

This time your job is to fill a sequence of N positive integers into a spiral matrix in non-increasing order. A spiral matrix is filled in from the first element at the upper-left corner, then move in a clockwise spiral. The matrix has m rows and n columns, where m and n satisfy the following: m*n must be equal to N; m>=n; and m-n is the minimum of all the possible values.

Input Specification:

Each input file contains one test case. For each case, the first line gives a positive integer N. Then the next line contains N positive integers to be filled into the spiral matrix. All the numbers are no more than 10⁴. The numbers in a line are separated by spaces.

Output Specification:

For each test case, output the resulting matrix in m lines, each contains n numbers. There must be exactly 1 space between two adjacent numbers, and no extra space at the end of each line.

Sample Input:

12
37 76 20 98 76 42 53 95 60 81 58 93

Sample Output:

98 95 93
42 37 81
53 20 76
58 60 76

 #include<stdio.h>
 #include<vector>
 #include<algorithm>
 #include<math.h>
 using namespace std;
 int ans[][];

 bool cmp(int a,int b)
 {
     return a > b;
 }
 int main()
 {
     int len,tem;
     scanf("%d",&len);
     vector<int> vv;
     for(int i =  ;i <= len ;++i)
     {
         scanf("%d",&tem);
         vv.push_back(tem);
     }
     sort(vv.begin(),vv.end(),cmp);
     int n,m;
     n = sqrt((double)len);
     while(len % n != )
     {
         --n;
     }
     m = len / n;
     int high = , low = m, left = ,right = n;
     int  x = ,y = ;
     for(int i =  ;i < len ;++i)
     {
         while(i < len && x <= right)
         {
             ans[y][x] = vv[i];
             ++i;
             ++x;
         }
         --x;
         ++y;
         ++high;
         while(i < len && y <= low)
         {
             ans[y][x] = vv[i];
             ++i;
             ++y;
         }
         --y;
         --x;
         --right;
         while(i < len && x >= left)
         {
             ans[y][x] = vv[i];
             ++i;
             --x;
         }
         ++x;
         --y;
         --low;
         while(i < len && y >= high)
         {
             ans[y][x] = vv[i];
             ++i;
             --y;
         }
         ++y;
         ++x;
         ++left;
         --i;
     }
     for(int i =  ;i <= m ;++i)
     {
         for(int k =  ;k <= n ;++k)
         {
             if(k == ) printf("%d",ans[i][k]);
             else printf(" %d",ans[i][k]);
         }
         printf("\n");
     }
     return ;
 }