题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=1711
Problem Description
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.
Input
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].
Output
For each test case, you should output one line which only contain K described above. If no such K exists, output -1 instead.
Sample Input
2 13 5 1 2 1 2 3 1 2 3 1 3 2 1 2 1 2 3 1 3 13 5 1 2 1 2 3 1 2 3 1 3 2 1 2 1 2 3 2 1
Sample Output
6 -1
Source
模板~~
代码:
#include <algorithm>
#include <cstdlib>
#include <iostream>
#include <cstring>
#include <cstdio>
#include <vector>
#include <cctype>
#include <cmath>
#include <stack>
#include <queue>
#include <list>
#include <map>
#include <set>
using namespace std;
#define min2(x, y) min(x, y)
#define max2(x, y) max(x, y)
#define min3(x, y, z) min(x, min(y, z))
#define max3(x, y, z) max(x, max(y, z))
#define clr(x, y) memset(x, y, sizeof(x))
#define fr(i,n) for(int i = 0; i < n; i++)
#define fr1(i,n) for(int i = 1; i < n; i++)
#define upfr(i,j,n) for(int i = j; i <= n; i++)
#define dowfr(i,j,n) for(int i = n; i >= j; i--)
#define scf(n) scanf("%d", &n)
#define scf2(n,m) scanf("%d %d",&n,&m)
#define scf3(n,m,p) scanf("%d %d %d",&n,&m,&p)
#define ptf(n) printf("%d",n)
#define ptf64(n) printf("%I64d",n)
#define ptfs(s) printf("%s",s)
#define ptln() printf("\n")
#define ptk() printf(" ")
#define ptc(c) printf("%c",c)
#define srt(a,n) sort(a,n)
#define LL long long
#define pi acos(-1.0)
#define eps 0.00001
#define maxn 1000005
#define mod 10000007
int str1[maxn], str2[maxn];
int nex[maxn];
int n,m;
void get_next(int str[])
{
int i = 1, j = 0;
nex[0] = -1;
while(i < m)
{
if(j == -1 || str[i] == str[j])
{
i ++;
j ++;
nex[i] = j;
}
else
j = nex[j];
}
}
int kmp(int str1[], int str2[])
{
int i = 0, j = 0;
get_next(str2);
while(i < n && j < m)
{
if(j == -1 || str1[i] == str2[j])
{
i ++;
j ++;
}
else
j = nex[j];
}
if(j == m)
return i - j;
return -1;
}
int main()
{
//freopen("in.txt","r",stdin);
int ca;
scf(ca);
while(ca--)
{
clr(nex, -1);
clr(str1, 0);
clr(str2, 0);
scf2(n, m);
int cnt1 = 0, cnt2 = 0;
int k;
fr(i, n)
{
scf(str1[i]);
}
fr(i, m)
{
scf(str2[i]);
}
int res = kmp(str1, str2);
if(res != -1)
printf("%d\n", res + 1);
else
printf("-1\n");
}
return 0;