import java.io.IOException; import java.io.InputStream; import java.io.PrintWriter; import java.util.Arrays; import java.util.NoSuchElementException; public class Main { public static void main(String[] args) { FastScanner scan = new FastScanner(); PrintWriter out = new PrintWriter(System.out); final int RIGHT = 0, DOWN = 1, LEFT = 2, UP = 3; int dx[] = { 1, 0, -1, 0 }; int dy[] = { 0, 1, 0, -1 }; int direc = RIGHT; int n = scan.nextInt(); int list[][] = new int[n][n]; int nx = 0, ny = 0; int v = 1; while(true) { list[ny][nx] = v; if(v == n*n) break; v++; nx += dx[direc]; ny += dy[direc]; if(direc == RIGHT) { if(nx+1 == n || list[ny][nx+1] != 0) { direc = DOWN; } } if(direc == DOWN) { if(ny+1 == n || list[ny+1][nx] != 0) { direc = LEFT; } } if(direc == LEFT) { if(nx-1 < 0 || list[ny][nx-1] != 0) { direc = UP; } } if(direc == UP) { if(ny-1 < 0 || list[ny-1][nx] != 0) { direc = RIGHT; } } } for(int i=0; i 0) out.print(" "); out.printf("%03d", list[i][j]); } out.println(); } out.flush(); } static class FastScanner { private final InputStream in = System.in; private final byte[] buffer = new byte[1024]; private int ptr = 0; private int buflen = 0; private boolean hasNextByte() { if (ptr < buflen) { return true; } else { ptr = 0; try { buflen = in.read(buffer); } catch (IOException e) { e.printStackTrace(); } if (buflen <= 0) { return false; } } return true; } private int readByte() { if (hasNextByte()) return buffer[ptr++]; else return -1; } private static boolean isPrintableChar(int c) { return 33 <= c && c <= 126; } private void skipUnprintable() { while (hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++; } public boolean hasNext() { skipUnprintable(); return hasNextByte(); } public String next() { if (!hasNext()) throw new NoSuchElementException(); StringBuilder sb = new StringBuilder(); int b = readByte(); while (isPrintableChar(b)) { sb.appendCodePoint(b); b = readByte(); } return sb.toString(); } public int nextInt() { return (int) nextLong(); } public long nextLong() { if (!hasNext()) throw new NoSuchElementException(); long n = 0; boolean minus = false; int b = readByte(); if (b == '-') { minus = true; b = readByte(); } if (b < '0' || '9' < b) { throw new NumberFormatException(); } while (true) { if ('0' <= b && b <= '9') { n *= 10; n += b - '0'; } else if (b == -1 || !isPrintableChar(b)) { return minus ? -n : n; } else { throw new NumberFormatException(); } b = readByte(); } } } }