public static int countString(String s){
        int num = 0 ; 
     String[] ss =    s.split("[\\+\\-\\*/\\(\\)]") ;
    if( ss.length>2){
     int si = 0 ;
    if( (si=s.indexOf("("))!=-1){
        num =    countString(s.substring(si+1 , s.indexOf(")")));
        num =countString(s.substring(0 , si)+num + s.substring(s.indexOf(")")+1));
    }else if((si=s.replaceAll("[\\*/]", ",").indexOf(","))!= -1 ){
        System.out.println(si);
        int statr = s.substring(0, si).replaceAll("[\\+\\-\\*/\\(\\)]", ",").lastIndexOf(",") ;
        int end = s.substring( si+1).replaceAll("[\\+\\-\\*/\\(\\)]", ",").indexOf(",") ;
        num =    countString(s.substring(statr==-1?0:statr, end==-1?s.length():end+2));
        num =countString(s.substring(0 , statr==-1?0:statr)+num + s.substring(end==-1?s.length():end+2));
    }else if((si=s.replaceAll("[\\+\\-]", ",").indexOf(","))!= -1 ){
        int statr = s.substring(0, si).replaceAll("[\\+\\-\\*/\\(\\)]", ",").lastIndexOf(",") ;
        int end = s.substring( si+1).replaceAll("[\\+\\-\\*/\\(\\)]", ",").indexOf(",") ;
        num =    countString(s.substring(statr==-1?0:statr, end==-1?s.length():end+2));
        num =  countString(s.substring(0 , statr==-1?0:statr)+num + s.substring(end==-1?s.length():end+2));
    }
    
    }else{
        int index =s.replaceAll("[\\+\\-\\*/\\(\\)]", ",").indexOf(",") ;
        if(index!=-1){
    String s2 =    s.substring(index,index+1) ;
        if(s2.equals("*"))
            num = new Integer(ss[0])  * new Integer(ss[1]) ;
        if(s2.equals("/"))
            num = new Integer(ss[0])  / new Integer(ss[1]) ;
        if(s2.equals("+"))
            num = new Integer(ss[0])  + new Integer(ss[1]) ;
        if(s2.equals("-"))
            num = new Integer(ss[0]) - new Integer(ss[1]) ;
    }else{
        num = new Integer(s)  ;
    }
    }
    
        return num;
    }

------解决方案--------------------
Java code


public static int countString(String s){
        System.out.println(s);
        int num = 0 ; 
     String[] ss =    s.split("[\\+\\-\\*/\\(\\)]") ;
    if( ss.length>2){
     int si = 0 ;
    if( (si=s.indexOf("("))!=-1){
        num =    countString(s.substring(si+1 , s.indexOf(")")));
        num =countString(s.substring(0 , si)+num + s.substring(s.indexOf(")")+1));
    }else if((si=s.replaceAll("[\\*/]", ",").indexOf(","))!= -1 ){
        int statr = s.substring(0, si).replaceAll("[\\+\\-\\*/\\(\\)]", ",").lastIndexOf(",") ;
        System.out.println(si);
        int end = s.substring( si+1).replaceAll("[\\+\\-\\*/\\(\\)]", ",").indexOf(",") ;
        num =    countString(s.substring(statr==-1?0:statr+1, end==-1?s.length():si+end+1));
        num =countString(s.substring(0 , statr==-1?0:statr+1)+num + s.substring(end==-1?s.length():si+end+1));
    }else if((si=s.replaceAll("[\\+\\-]", ",").indexOf(","))!= -1 ){
        if(si==0){
            num =  countString("&"+s.substring(1) );
        }else{
        int statr = s.substring(0, si).replaceAll("[\\+\\-\\*/\\(\\)]", ",").lastIndexOf(",") ;
        int end = s.substring( si+1).replaceAll("[\\+\\-\\*/\\(\\)]", ",").indexOf(",") ;
        num =    countString(s.substring(statr==-1?0:s