Adding 50 to string numbers

        String str = "Some3people6love20code102";
        String newstr = "";
        String tmp = "";
        for (int i = 0; i<str.length(); i++){
            if((int)str.charAt(i) >= 48 && (int)str.charAt(i) <= 57){
                tmp += str.charAt(i);
            }else{
                if(tmp.length()>0){
                    newstr+=((Integer.parseInt(tmp)+50)+"");
                }
                newstr+=str.charAt(i);
                tmp = "";
            }
            System.out.println(newstr);
        }
        if(tmp.length()>0){
            newstr+=((Integer.parseInt(tmp)+50)+"");
        }
        System.out.println(newstr);