KMP裸题了,只不过把字符改成数字。
/*
* @Author: hesorchen
* @Date: 2020-07-02 22:19:34
* @LastEditTime: 2020-07-11 12:36:53
* @Description: https://hesorchen.github.io/
*/
#include <map>
#include <set>
#include <list>
#include <queue>
#include <deque>
#include <cmath>
#include <stack>
#include <vector>
#include <cstdio>
#include <string>
#include <cstdlib>
#include <cstring>
#include <iostream>
#include <algorithm>
using namespace std;
#define endl '\n'
#define PI acos(-1)
#define PB push_back
#define ll long long
#define INF 0x3f3f3f3f
#define mod 1000000007
#define pll pair<ll, ll>
#define lowbit(abcd) (abcd & (-abcd))
#define max(a, b) ((a > b) ? (a) : (b))
#define min(a, b) ((a < b) ? (a) : (b))
#define IOS \
ios::sync_with_stdio(false); \
cin.tie(0); \
cout.tie(0);
#define FRE \
{ \
freopen("in.txt", "r", stdin); \
freopen("out.txt", "w", stdout); \
}
inline ll read()
{
ll x = 0, f = 1;
char ch = getchar();
while (ch < '0' || ch > '9')
{
if (ch == '-')
f = -1;
ch = getchar();
}
while (ch >= '0' && ch <= '9')
{
x = (x << 1) + (x << 3) + (ch ^ 48);
ch = getchar();
}
return x * f;
}
//==============================================================================
ll nxt[1000010];
ll a[1000010], b[1000010];
ll lena, lenb;
void get_nxt()
{
int j = 0, k = -1;
nxt[0] = -1;
while (j < lenb)
{
if (k == -1 || b[j] == b[k])
nxt[++j] = ++k;
else
k = nxt[k];
}
}
int KMP()
{
get_nxt();
ll i = 0, j = 0;
while (i < lena)
{
if (j == -1 || a[i] == b[j])
i++, j++;
else
j = nxt[j];
if (j == lenb)
return i - j + 1;
}
return 0;
}
int main()
{
IOS;
ll n;
cin >> n;
while (n--)
{
cin >> lena >> lenb;
for (int i = 1; i <= lena; i++)
cin >> a[i - 1];
for (int i = 1; i <= lenb; i++)
cin >> b[i - 1];
cout << (KMP() ? KMP() : -1) << endl;
}
return 0;
}
/*
ababa
aba
*/