hd 1988 Flipping Burned Pancakes

hd 1988 Flipping Burned Pancakes

做练习赛时,没来的及看.后来看的时候发现可以用bfs+递归求解,写好后TLE,后来又改成了dfs,一样TLE.后来又问了WY,直接构造就可以了,方法是先排大的,再排小的.
/**/ /*
方法:直接构造,先排大的,再排小的...
*/
#include  < iostream >
#include  < queue >
using   namespace  std;
int  a[ 32 ], n;
void  change( int  t)
... {
    int i;
    for (i=1; i<=t; ++i)
    ...{
        a[i] *= -1;
    }
    for (i=1; i<=t/2; ++i)
    ...{
        int tt = a[i];
        a[i] = a[t-i+1];
        a[t-i+1] = tt;
    }
}
int  main()
... {
    int i, j, index = 1;
    int N;
    char c;
    queue<int> mq;
    scanf("%d", &N);
    while (N--)
    ...{
        scanf("%d", &n);
        for (i=1; i<=n; ++i)
        ...{
            scanf(" %c%d", &c, &a[i]);
            if(c == '-')
                a[i] *= -1;
        }    
        for (i=n; i>=1; --i)
        ...{
            if(a[i] != i)
            ...{
                while (1)
                ...{
                    for (j=1; j<=n; ++j)
                    ...{
                        if(abs(a[j]) == i)
                            break;
                    }
                    if(j==1 && a[j]==-i)
                    ...{
                        change(i);
                        mq.push(i);
                        break;
                    }
                    else
                    ...{
                        change(j);
                        mq.push(j);
                    }
                }
            }
        }
        printf("%d %d", index++, mq.size());
        while (!mq.empty())
        ...{
            printf(" %d", mq.front());
            mq.pop();
        }
        printf(" ");
    }
    return 0;
}