poj2255

简单题

#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cstring>
using namespace std;

#define maxn 27

char pre[maxn], in[maxn], post[maxn];
int len;

int find(int l, int r, char ch)
{
    for (int i = l; i < r; i++)
        if (in[i] == ch)
            return i;
    return -1;
}

void make(int prel, int prer, int inl, int inr)
{
    if (prel >= prer)
        return;
    if (prel == prer - 1)
    {
        printf("%c", pre[prel]);
        return;
    }
    int pos = find(inl, inr, pre[prel]);
    make(prel + 1, prel + pos - inl + 1, inl, pos);
    make(prel + pos - inl + 1, prer, pos + 1, inr);
    printf("%c", pre[prel]);
}

int main()
{
    //freopen("t.txt", "r", stdin);
    while (scanf("%s%s", pre, in) != EOF)
    {
        len = strlen(pre);
        make(0, len, 0, len);
        printf("\n");
    }
    return 0;
}