864
Japan  's two biggest operators NTT DoCoMo and  KDDI  said Wednesday they are jointly developing a system to notify customers of an imminent earthquake while number three Softbank said it is separately working on a similar service .
 country of headquarters: Japan, KDDI
Given a phrase that describes the relationship between two words, extract the words and the lexical relationship between them. The output format should be "relation1: word1, word2; relation2: word3, word4". 
Option: cities of residence, top members employees, members, alternate names, origin, state or provinces of residence, title of person, spouse, city of headquarters, NA, founded by, state or province of headquarters, employee of, countries of residence, country of birth, founded, subsidiaries, country of headquarters 
Text: {0} 
Answer:
 country of headquarters: Japan, KDDI