1 public class Solution 2 { 3 public int MinDominoRotations(int[] A, int[] B) 4 { 5 var na = A.Length; 6 var nb = B.Length; 7 if (na != nb) 8 { 9 return -1;10 }11 var dic1 = new Dictionary >();12 var dic2 = new Dictionary
>();13 for (var i = 1; i <= 6; i++)14 {15 dic1.Add(i, new List
());17 }18 19 for (var i = 0; i < na; i++)20 {21 var a = A[i];22 dic1[a].Add(i);23 24 var b = B[i];25 dic2[b].Add(i);26 }27 28 var minchanges = na;29 var find = false;30 for (var i = 1; i <= 6; i++)31 {32 var top = dic1[i];33 var bottom = dic2[i];34 var temp = top.Union(bottom).Distinct();35 if (temp.Count() == na)36 {37 minchanges = Math.Min(minchanges, na - Math.Max(top.Count(), bottom.Count()));38 find = true;39 }40 }41 return find ? minchanges : -1;42 }43 }