POJ2255（二叉树遍历）

/*
ID: LinKArftc
PROG: 2255.cpp
LANG: C++
*/

#include <map>
#include <set>
#include <cmath>
#include <stack>
#include <queue>
#include <vector>
#include <cstdio>
#include <string>
#include <utility>
#include <cstdlib>
#include <cstring>
#include <iostream>
#include <algorithm>
using namespace std;
#define eps 1e-8
#define randin srand((unsigned int)time(NULL))
#define input freopen("input.txt","r",stdin)
#define debug(s) cout << "s = " << s << endl;
#define outstars cout << "*************" << endl;
const double PI = acos(-1.0);
const double e = exp(1.0);
const int inf = 0x3f3f3f3f;
const int INF = 0x7fffffff;
typedef long long ll;

const int maxn = 30;

char str[maxn];
int cur;

void build(char *str1, char *str2, int len) {
    if (len <= 0) return;
    int pos = strchr(str2, str1[0]) - str2;
    build(str1 + 1, str2, pos);
    build(str1 + pos + 1, str2 + pos + 1, len - pos - 1);
    printf("%c", str1[0]);
}

char str1[maxn], str2[maxn];

int main() {
    while (~scanf("%s %s", str1, str2)) {
        cur = 0;
        build(str1, str2, strlen(str1));
        printf("\n");
    }

    return 0;
}