package yukicoder;

import java.util.Scanner;

public class Yuki24_{
	
	public static void main(String[] args) {
		
		Scanner scan = new Scanner(System.in);
		int num = scan.nextInt();
		int arr[][] = new int[num][4];
		String[] ans = new String[num];
		int numbers[] = new int[10];
		
		for (int i = 0; i < num; i++ ) {
			for (int j = 0; j < 4; j++ ) {
				arr[i][j] = scan.nextInt();
			}
			ans[i] = scan.next(); 
		}
		scan.close();
		
		for (int i = 0; i < num; i++ ) {
			for (int j = 0; j < 4; j++ ) {
				if("YES".equals(ans[i])){
					numbers[arr[i][j]] += 1;
				}
				if("NO".equals(ans[i])){
					numbers[arr[i][j]] -= 1;
				}
			}
		}
		
		int jug = 0;
		for(int i = 0 ;i <= 9; i++ ) {
			if(jug <= numbers[i]){
				jug = i;
			}
		}
		System.out.println(jug);	
	}
}