for ( int i = str.length();i>2;i=i-3)
{
str.insert(i-3,',');
}
{
str.insert(i-3,',');
}
2017-05-22
public static char getRandomCharacter(char ch1,char ch2){
return (char)(ch1+Math.random()*(ch2-ch1+1));
}
getRandomCharacter('a','z')
getRandomCharacter('A,'Z')
getRandomCharacter('0','9')
return (char)(ch1+Math.random()*(ch2-ch1+1));
}
getRandomCharacter('a','z')
getRandomCharacter('A,'Z')
getRandomCharacter('0','9')
2017-05-22