include <stdio.h>

int main(){
char a;
int count1 = 0;
int count2 = 0;
while((a=getchar()) != '0' && (a!=EOF))
{
if(a == 'A')
count1++;
else
count2++;
}
if(count1 > count2)
{
printf("A");
}
else if(count1 < count2)
printf("B");
else
printf("E");
return 0;
}
注意输出的字符 必须是双引号