there n city number 0 n 1 n 1 road way travel different city network form tree last year the ministry transport decide orient road direction narrowroad represent connection connectionsi ai bi represent road city ai city bithis year big event capital city 0 people want travel cityYour task consist reorient road city visit city 0 return minimum number edge changedits guarantee city reach city 0 reorder Example 1input n 6 connection 0113234045output 3explanation Change direction edge red node reach node 0 capitalExample 2input n 5 connection 10123234output 2explanation Change direction edge red node reach node 0 capitalExample 3input n 3 connection 1020output 0 Constraints2 n 5 104connectionslength n 1connectionsilength 20 ai bi n 1ai bi