USACO 5.5 Hidden Password(搜索+优化)

水了好几下。

优化1：开始初始化的时候，如果左边那个也是最小值，那么此点就不用进队了。

优化2:如果队列里的位置，已经超过了后面位置的初始位置，那么后面这个位置也没用了。

 /*
 ID: cuizhe
 LANG: C++
 TASK: hidden
 */
 #include <cstdio>
 #include <cstring>
 #include <string>
 #include <cmath>
 #include <algorithm>
 using namespace std;
 int que1[],que2[];
 char str[];
 int main()
 {
     int i,len,minz,num,tnum,temp;
     char ch;
     freopen("hidden.in","r",stdin);
     freopen("hidden.out","w",stdout);
     scanf("%d",&len);
     for(i = ;i < len;)
     {
         scanf("%c",&ch);
         if(ch != '\n')
         str[i++] = ch;
     }
     for(i = len;i < *len;i ++)
     {
         str[i] = str[i-len];
     }
     minz = ;
     num = ;
     for(i = ;i < len;i ++)
     {
         if(minz > str[i]-'a')
         {
             num = ;
             minz = str[i]-'a';
             que1[num++] = i;
         }
         else if(minz == str[i]-'a')
         {
             if(i != &&str[i-]-'a' == minz)
             continue;//优化1
             que1[num++] = i;
         }
     }
     for(temp = ;;temp ++)
     {
         if(num == ) break;
         minz = ;
         for(i = ;i < num;i ++)
         {
             if(minz > str[que1[i]+]-'a')
             {
                 minz = str[que1[i]+]-'a';
                 tnum = ;
                 que2[tnum++] = que1[i]+;
             }
             else if(minz == str[que1[i]+]-'a')
             {
                  if(que2[tnum-] >= que1[i]+ -temp)
                  continue;//优化2
                  que2[tnum++] = que1[i]+;
             }
         }
         for(i = ;i < tnum;i ++)
         que1[i] = que2[i];
         num = tnum;
     }
     printf("%d\n",que1[]-temp);
     return ;
 }