又复习了一遍kmp….之前都忘光了
#include<bits/stdc++.h>
using namespace std;
#define pb(x) push_back(x)
#define ll long long
#define mk(x, y) make_pair(x, y)
#define lson l, m, rt<<1
#define mem(a) memset(a, 0, sizeof(a))
#define rson m+1, r, rt<<1|1
#define mem1(a) memset(a, -1, sizeof(a))
#define mem2(a) memset(a, 0x3f, sizeof(a))
#define rep(i, a, n) for(int i = a; i<n; i++)
#define ull unsigned long long
typedef pair<int, int> pll;
const double PI = acos(-1.0);
const double eps = 1e-;
const int mod = 1e9+;
const int inf = ;
const int dir[][] = { {-, }, {, }, {, -}, {, } };
const int maxn = 1e6+;
int next[maxn], a[maxn], vis[maxn], used[maxn];
char s[maxn];
void get_next() {
int len = strlen(s);
int i = , j = -;
next[] = -;
while(i<len) {
if(j==- || s[i] == s[j]) {
i++, j++;
next[i] = j;
} else {
j = next[j];
}
}
int pos = next[len];
while(pos != -) {
vis[pos] = ;
pos = next[pos];
}
return ;
}
int main()
{
int n, m;
cin>>n>>m;
scanf("%s", s);
int len = strlen(s);
get_next();
for(int i = ; i<=m; i++) {
scanf("%d", &a[i]);
}
sort(a+, a+m+);
int flag = ;
for(int i = ; i<=m; i++) {
if(i == || a[i]-a[i-]>len) {
for(int j = a[i]; j<len+a[i]; j++) {
used[j] = ;
}
} else {
if(vis[len+a[i-]-a[i]]) {
for(int j = a[i-]+len; j<len+a[i]; j++) {
used[j] = ;
}
} else {
flag = ;
break;
}
}
}
if(flag) {
puts("");
return ;
}
ll ans = ;
for(int i = ; i<=n; i++) {
if(!used[i]) {
ans = (ans*)%mod;
}
}
cout<<ans<<endl;
return ;
}