习题6.37

 

//6.37前序和中序序列建立二叉链表BiTree buildbyprein(char pre[],char in[],int L1,int H1 ,int L2,int H2 ){BiTree T;if (L1 <= H1){T = (BiTree)malloc(sizeof(BiTNode)) ;T -> data = pre[L1] ;for (int i = L2 ; i <= H2 ;++i)if(in[i] == pre[L1])break ;T -> lchild = buildbyprein(pre , in , L1 + 1 , L1 + i - L2 , L2 , i - 1) ;T -> rchild = buildbyprein(pre , in , L1 + i - L2 + 1 , H1 , i + 1 , H2) ;}elseT = null ;return T ;}