HDU-1711(Number Sequence)

HDU-1711

kmp模板题

#include 
#include 
#include 

using namespace std;

const int maxn = 1000005;
const int maxm = 10005;
int Next[maxm];
int target[maxn];
int pattern[maxm];


void getNext(int ne[], int s[], int len)
{
    ne[0] = -1;
    int i = 0, j = -1;

    while(i < len)
    {
        if(j == -1 || s[j] == s[i])
        {
            i++;
            j++;
            ne[i] = j;
        }else
            j = ne[j];
    }
}

int main()
{
    int t;
    int n, m;

    scanf("%d", &t);
    while(t--)
    {
        memset(Next, 0, sizeof(Next));
        scanf("%d%d", &n, &m);
        for(int i = 0; i < n; ++i) scanf("%d", &target[i]);
        for(int j = 0; j < m; ++j) scanf("%d", &pattern[j]);
        getNext(Next, pattern, m);
        int i = 0, j = 0;
        while(i < n && j < m)
        {
            if(j == -1 || target[i] == pattern[j])
            {
                i++;
                j++;
            }else{
                j = Next[j];
            }
        }
        if(j == m)printf("%d\n", i - j + 1);
        else printf("-1\n");
    }
    return 0;
}