设计算法实现求两个集合的交集的运算A？
Array A = new Array[M];Array B = new Array[N];Array C = new Array[M+N];int i = 0;foreach(int k in ListA){ A[i] = k;i++;}int = 1foreach(int k in ListB){ B[N-i] = k;i--;}Merge(A,B,C);复杂度o(M+N)
