DFS Gym 100553J Jokewithpermutation

题目传送门

 /*
     题意：将字符串分割成一个全排列
     DFS：搜索主要在一位数和两位数的处理，用d1, d2记录个数，在不饱和的情况下，两种都试一下
         DFS还是写不来，难道是在家里懒？
 */
 #include <cstdio>
 #include <algorithm>
 #include <cstring>
 #include <cmath>
 using namespace std;

 const int MAXN = 1e2 + ;
 const int INF = 0x3f3f3f3f;
 char s[MAXN];
 bool vis[];
 int ans[];
 int len, tot, n1, n2;

 bool DFS(int d1, int d2, int p, int cnt)
 {
     if (cnt == tot)    return true;
     if (d1 < n1)
     {
         int x = s[p] - '';
         if (x !=  && !vis[x])
         {
             vis[x] = true;    ans[cnt+] = x;
             if (DFS (d1+, d2, p+, cnt+))    return true;
             vis[x] = false;
         }
     }
     if (d2 < n2)
     {
         int x = (s[p] - '') *  + (s[p+] - '');
         if (x >=  && x <= tot && !vis[x])
         {
             vis[x] = true;    ans[cnt+] = x;
             if (DFS (d1, d2+, p+, cnt+))    return true;
             vis[x] = false;
         }
     }

     return false;
 }

 int main(void)        //Gym 100553J Jokewithpermutation
 {
 //    freopen ("J.in", "r", stdin);
     freopen ("joke.in", "r", stdin);
     freopen ("joke.out", "w", stdout);

     while (scanf ("%s", s + ) == )
     {
         memset (vis, false, sizeof (vis));
         len = strlen (s + );
         tot = (len + ) / ;
         if (tot <= )
         {
             for (int i=; i<=len; ++i)
             {
                 printf ("%c%c", s[i], (i==len) ? '\n' : ' ');
             }
         }
         else
         {
             n1 = ;    n2 = tot - ;
             DFS (, , , );
             for (int i=; i<=tot; ++i)
             {
                 printf ("%d%c", ans[i], (i==tot) ? '\n' : ' ');
             }
         }
     }

     return ;
 }