java，字符串课后练习

public class zhifuchuan {

    public static void main(String[] args) {
        String str="mingrikejijavabu";

        int a=str.length();
        int b=str.replace("i", "").length();
        System.out.println("i出现的个数"+(a-b));
        
        
        
        
        

    }

}