find the post order form inorder and pereddr
#include <stdio.h>
int find_value(int p, int in_order[], int n) {
for (int i = 0; i < n; ++i) {
if (in_order[i] == p) {
return i;
}
}
return -1;
}
int postorder(int pre_order[], int in_order[], int n) {
int root = find_value(pre_order[0], in_order, n);
if(root !=0 )
postorder(pre_order+1, in_order, root);
if (root != n-1)
postorder(pre_order+root+1, in_order+root+1, n-root-1);
printf("%d ", pre_order[0]);
}
int main(int argc, char const *argv[]) {
int pre_order[] = {1, 2, 4, 5, 3, 6};
int in_order[] = {4, 2, 5, 1, 3, 6};
int size = sizeof(pre_order)/sizeof(pre_order[0]);
postorder(pre_order, in_order, size);
return 0;
}