in addition complaint lighting lot complaint insufficient radio signal covering receive Bertown city hall recently n complaint send mayor suspiciosly similar ith complaint radio fan mention signal radio station x_i y_i cover part city demand signal station receive cityOf cousre mayor Bertown currently work satisfy complaint a new radio tower instal Bertown transmit signal integer power 1 M let denote signal power f the mayor decide choose set radio station establish contract choose station to establish contract ith station follow condition meet signal power f l_i signal ith station will not cover city signal power f great r_i signal receive resident town have not establish contract ith station all information mayor realise choose station hard but consulting specialist learn station signal station interfere m pair station u_i v_i use signal frequency pair impossible establish contract station if station x y use frequency y z use frequency imply x z use frequenciesthe mayor find hard analyze situation hire help you choose signal power f set station establish contract complaint satisfy formally 1 n city establish contract station x_i station y_i choose station interfere formally 1 m city establish contract station u_i station v_i choose station condition signal power meet formally choose station condition l_i le f le r_i meet