#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<ll, ll> pp;
#define rep(i,l,r) for(int i = (l); i < (r); i++)
#define per(i,r,l) for(int i = (r); i >= (l); i--)
#define sz(x) (int)x.size()
#define all(x) begin(x), end(x)
#define pb puhs_back
#define ff first
#define ss second
void dbg(){
cerr << endl;
}
template<typename Head, typename... Tail> dbg(Head h, Tail... t){
cerr<< " " << h << ",";
dbg(t...);
}
#define er(...) cerr << __LINE__ << " <" << #__VA_ARGS__ << ">:", dbg(__VA_ARGS__)
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
void IOS(){
cin.tie(0) -> sync_with_stdio(0);
// #ifndef ONLINE_JUDGE
// freopen("inp.txt", "r", stdin);
// freopen("out.txt", "w", stdout);
// #define er(...) cerr << __LINE__ << " <" << #__VA_ARGS__ << ">:", dbg(__VA_ARGS__)
// #else
// #define er(...) 0
// #endif
}
const ll mod = 1e9 + 7, mod2 = 1e9 + 9, maxn = 5e5 + 5, lg = 20, inf = ll(1e9) + 5, p = 9973;
map<pair<int, int>, bool> is;
void add(string s){
pp hsh = {0, 0};
for(char c: s){
hsh.ff = (hsh.ff*p + c - 'a' + 1)%mod;
hsh.ss = (hsh.ss*p + c - 'a' + 1)%mod2;
is[hsh] = true;
}
}
ll pw1[maxn], pw2[maxn];
pp hsh[maxn];
void build_hash(string s){
rep(i,0,sz(s)){
hsh[i].ff = ((i?hsh[i-1].ff:0)*p + s[i] - 'a' + 1)%mod;
hsh[i].ss = ((i?hsh[i-1].ss:0)*p + s[i] - 'a' + 1)%mod2;
}
pw1[0] = pw2[0] = 1;
rep(i,1,sz(s) + 1){
pw1[i] = pw1[i-1]*p%mod;
pw2[i] = pw2[i-1]*p%mod2;
}
}
pair<int, int> get_hsh(int l, int r){
return {
(hsh[r].ff - (l?hsh[l-1].ff*pw1[r-l+1]%mod:0) + mod)%mod,
(hsh[r].ss - (l?hsh[l-1].ss*pw2[r-l+1]%mod2:0) + mod2)%mod2
};
}
int nxt[maxn][lg], nxt_id[maxn][lg];
pair<int, int> rmq[maxn][lg];
int lgg[maxn], m;
void build_rmq(int x){
m++;
rep(i,0,m) rmq[i][0] = {nxt[i][x], i};
rep(i,2,m + 1) lgg[i] = lgg[i>>1] + 1;
rep(j,1,lg){
rep(i,0,m - (1<<j) + 1){
rmq[i][j] = max(rmq[i][j-1], rmq[i+(1<<(j-1))][j-1]);
}
}
m--;
}
pp get_rmq(int l, int r){
int k = lgg[r - l + 1];
return max(rmq[l][k], rmq[r-(1<<k)+1][k]);
}
int main(){ IOS();
int n, q; cin >> n >> q;
rep(i,0,n){
string t; cin >> t;
add(t);
}
string s; cin >> s;
build_hash(s);
m = sz(s);
rep(j,0,lg) nxt[m][j] = nxt_id[m][j] = m;
rep(i,0,m){
int lx = i-1, rx = m;
while(lx + 1 < rx){
int mid = (lx + rx)>>1;
if(is[get_hsh(i, mid)]) lx = mid;
else rx = mid;
}
nxt[i][0] = rx;
// er(i, rx);
}
build_rmq(0);
rep(i,0,m){
nxt_id[i][0] = get_rmq(i, nxt[i][0]).ss;
// er(i, nxt_id[i][0]);
}
rep(j,1,lg){
rep(i,0,m){
nxt[i][j] = nxt[nxt_id[i][j-1]][j-1], nxt_id[i][j] = nxt_id[nxt_id[i][j-1]][j-1];
}
}
while(q--){
int l, r; cin >> l >> r; r--;
// er(r, nxt[l][lg-1]);
if(nxt[l][lg-1] <= r) cout << -1 << '\n';
else{
int ans = 0;
per(i,lg-1,0){
int nx = nxt[l][i];
if(nx <= r){
ans |= 1<<i;
l = nxt_id[l][i];
}
}
cout << ans + 1 << '\n';
}
}
return 0;
}
Compilation message
Main.cpp:18:43: error: ISO C++ forbids declaration of 'dbg' with no type [-fpermissive]
18 | template<typename Head, typename... Tail> dbg(Head h, Tail... t){
| ^~~
Main.cpp: In function 'int dbg(Head, Tail ...)':
Main.cpp:21:1: warning: no return statement in function returning non-void [-Wreturn-type]
21 | }
| ^
