public class Action {
static int count = 0,i=0;
public static void digui(String num){
char[] num1 = num.toCharArray();
if(count
if (num1[i]=='a') {
count++;
}i++;
digui(num);
}
if(i>=num1.length) return;
}
public static void main(String[] args) {
digui("aaafdtfdsg");
System.out.println("a的个数:"+count);
}
}