백준 1058 - 친구

import java.io.FileInputStream;
import java.util.Scanner;
 
/*
 3
NYY
YNY
YYN
  * */
public class Main {
    static int N;
    static char[] cmap;
    static int[][] map;
    static int result;
    
    public static void main(String[] args) throws Exception{
        Scanner sc = new Scanner(System.in);
        N = sc.nextInt();
        map = new int[N][N];
        
        for(int i = 0; i<map.length; i++) {
            String c = sc.next();
            cmap = c.toCharArray();
            for(int j = 0; j<map[i].length; j++) {
                if(cmap[j] =='Y') {
                    map[i][j] = 1;
                }else {
                    map[i][j] = 9999;
                }
            }
        }
                
        for(int i = 0; i<N; i++) {
            for(int j = 0 ; j<N; j++) {
                for(int k = 0 ; k<N; k++) {
                    if(i == j|| j==k || i==k) {
                        continue;
                    }else if(map[i][j] > map[i][k] + map[k][j]) {
                        map[i][j] = map[i][k] + map[k][j];
                    }
                }
            }
        }
        
        for(int i = 0; i<map.length; i++) {
            int sum = 0;
            for(int j = 0 ; j<map[i].length; j++) {
                if(i==j) continue;
                else if(map[i][j] <=2 ) sum++;
            }
            result = Math.max(result, sum);
        }
        System.out.println(result);        
        
    }
 
}