#include <stdio.h>

const int l = 50000;
const int m = 5000;

int main() {
	for(int i = 0; i < l; i++) { printf(i % 2 == 0 ? "A" : "B"); }
	printf("\n%d\n", m);
	char s[] = "ABABABABAB";
	int c = 0;
	while(c < m) {
		printf("%s\n", s);
		
		int d = 9;
		while(s[d] == 'Z') { s[d] = 'A'; d--; }
		s[d]++;	
		
		c++;
	}
	
	return 0;
}