We want a program to check whether the brackets and quotation marks in our strings are balanced or not. By "balanced" we mean each opening bracket (quotation mark) has a corresponding closing bracket (quotation mark), and brackets (quotation marks) are properly nested. The program only needs to check the following six types of characters:
| opening curly bracket | { |
| closing curly bracket | } |
| opening square bracket | [ |
| closing square bracket | ] |
| opening round bracket | ( |
| closing round bracket | ) |
| opening/closing double quoatation mark | " |
| opening/closing single quoatation mark | ' |
For spaces and other characters in a string, our program can ignore them.
The following exampling strings are not balanced:
| strings | notes |
| ( a [ b ) ] | clearly, the square brackets are not properly nested with others |
| a " ( ' b ) c " ' | clearly, the single quoation marks are not properly nested with others |
| { " a ' ' " bcd | The first opening curly bracket does not has a corresponding closing bracket |
There are more than one lines, each line being a string for our program to check.
Please note that all the characters of an input line belong to the string. Please do not view the line as a C/C++/Python string in which single and double qouatation marks stand for delimiters.
For each string in the input, if the string is good, please output "OK", followed by a colon mark and a space, then the string.
Otherwise, please output "NG", followed by a colon mark and a space, then the string.