Given two sequences of numbers : a[1], a[2], ...... , a[N], and b[1], b[2], ...... , b[M] (1 <= M <= 10000, 1 <= N <= 1000000). Your task is to find a number K which make a[K] = b[1], a[K + 1] = b[2], ...... , a[K + M - 1] = b[M]. If there are more than one K exist, output the smallest one.

The first line of input is a number T which indicate the number of cases. Each case contains three lines. The first line is two numbers N and M (1 <= M <= 10000, 1 <= N <= 1000000). The second line contains N integers which indicate a[1], a[2], ...... , a[N]. The third line contains M integers which indicate b[1], b[2], ...... , b[M]. All integers are in the range of [-1000000, 1000000].

For each test case, you should output one line which only contain K described above. If no such K exists, output -1 instead.

213 51 2 1 2 3 1 2 3 1 3 2 1 21 2 3 1 313 51 2 1 2 3 1 2 3 1 3 2 1 21 2 3 2 1

6-1代码实现：   
   #include 
    
     #include 
     
      using namespace std;int next[10005];int a[1000005],b[10005];void getNext(int *b,int m,int n){    int i=0,j=-1;    next[0]=-1;    while(i
      
       >t;    while(t--)    {        cin>>m>>n;        for(int i=0;i
       
        >a[i];        }        for(int j=0;j
        
         >b[j];        }        getNext(b,m,n);        int i=0,j=0,flag=0;        while(i