Sonya like ice cream she eat programming competition that girl decide want open ice cream shopsSonya live city n junction n1 street all street twoway connect junction it possible travel junction street City Hall allow opening shop junction the girl open shop middle street Sonya exactly k friend trust if open shop friend work allow anybody eat ice cream pay since Sonya want skip important competition work shop personallySonya want ice cream shop form simple path length r 1 le r le k ie locate different junction f_1 f_2 dot f_r street f_i f_i1 1 r1the girl take care potential buyer wants minimize maximum distance junction near ice cream shop the distance junction b equal sum street length need pass junction junction b so Sonya want minimizemax_a min_1 le le r d_af_iwhere take value possible n junction f_i junction ith Sonyas shop locate d_xy distance junction x ySonya sure find optimal shop location ask help open k shop form simple path maximum distance junction near shop minimal