import java.util.*;
import java.lang.*;
class Main
{
{
String str
= "[[123,345,768]]"; String repl
= str.
replaceAll("([]\\[]){2,}",
"$1"); System.
out.
printf("repl=%s%n", repl
); }
}
aW1wb3J0IGphdmEudXRpbC4qOwppbXBvcnQgamF2YS5sYW5nLio7CgpjbGFzcyBNYWluCnsKCXB1YmxpYyBzdGF0aWMgdm9pZCBtYWluIChTdHJpbmdbXSBhcmdzKSB0aHJvd3MgamF2YS5sYW5nLkV4Y2VwdGlvbgoJewpTdHJpbmcgc3RyID0gIltbMTIzLDM0NSw3NjhdXSI7ClN0cmluZyByZXBsID0gc3RyLnJlcGxhY2VBbGwoIihbXVxcW10pezIsfSIsICIkMSIpOwpTeXN0ZW0ub3V0LnByaW50ZigicmVwbD0lcyVuIiwgcmVwbCk7Cgl9Cn0=