you mayor Berlyatov there n district m twoway road the ith road connect district x_i y_i the cost travel road w_i there path pair district city connectedThere k delivery route Berlyatov the ith route go district a_i district b_i there courier route courier choose cheap minimum total cost path district a_i district b_i deliver productsthe route district courier route coincide count independentlyyou road cost zero ie choose road change cost 0let dx y cheap cost travel district x yyour task find minimum total courier route cost achieve optimally select road change cost 0 in word find minimum possible value sumlimits_i 1k da_i b_i apply operation describe optimally