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 <iostream>
#include<vector>
#include <algorithm>

using namespace std;

void setSize(int &row, int &column, int N)
{
    int x = row-column;
    int r = row;
    int c = column;
    while(r>c)
    {
        r--;
        if(N%r!=0) continue;
        else
        {   c = N/r;
            if(r<c) return;
            else if(x>(r-c))
            {
                row = r;
                column = c;
                x = r-c;
            }
        }
    }
}
void inputArr(vector<int> arr,vector<vector<int> > &m, int row, int column, int r, int c, int n, int N)
{
    if(n==N) return;
    for(int i=0; i<column&&n!=N; i++) m[r][++c] = arr[n++];
    row--;
    for(int i=0; i<row&&n!=N; i++) m[++r][c] = arr[n++];
    column--;
    for(int i=0; i<column&&n!=N; i++) m[r][--c] = arr[n++];
    row--;
    for(int i=0; i<row&&n!=N; i++) m[--r][c] = arr[n++];
    column--;
    inputArr(arr,m,row,column,r,c,n,N);

}
bool compare(int a, int b){return a>b;}

int main()
{
    int N;
    int temp;
    int row;
    int column;
    vector<int> arr;
    vector<vector<int> > m;
    cin >> N;
    for(int i=0; i<N; i++)
    {
        cin >> temp;
        arr.push_back(temp);
    }
    sort(arr.begin(),arr.end(),compare);
    row = N;
    column = 1;
    setSize(row,column,N);
    m.resize(row,vector<int>(column));
    inputArr(arr,m,row,column,0,-1,0,N);
    for(int i=0; i<row; i++)
    {
        for(int j=0; j<column; j++)
        {
            if(j!=0) cout << " ";
            cout << m[i][j];
        }
        cout << endl;
    }
    return 0;
}