// Bismillahir Rahmanir Rahim //
// After hardship comes ease //
// AUTHOR : iamarman //
// pragmas
// #pragma GCC optimize("Ofast")
// #pragma GCC target("avx,avx2,fma")
// #pragma GCC optimization ("unroll-loops")
// #pragma GCC optimization ("strict-overflow")
#include<bits/stdc++.h>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>
using namespace std;
using namespace __gnu_pbds;
//// TEMPLATE ////
//---------------------------------------------------------------------------------------------------------------------------------|
# define el '\n'
# define sp " "
# define ff first
# define ss second
# define ll long long
# define pb push_back
# define mp make_pair
# define yess1 cout<<1<<el
# define noo cout<<"NO"<<el
# define yess cout<<"YES"<<el
# define siz(x) (int)x.size()
# define ull unsigned long long
# define all(v) v.begin(),v.end()
# define allr(v) v.rbegin(),v.rend()
# define torad(x) ((x) * ((2*acos(0))/180.0))
# define todeg(x) ((x) * (180.0/(2*acos(0))))
constexpr ll mod=998244353;
constexpr ll INF=2e18;
constexpr double PI= acos(-1);
constexpr double eps=1e-9;
# define mem(a,b) memset(a,b,sizeof(a))
# define sqr(a) ((a)*(a))
# define lcm(a,b) (a*b)/__gcd(a,b)
# define optimise { ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL); }
# define fraction(a) cout.unsetf(ios::floatfield); cout.precision(a); cout.setf(ios::fixed,ios::floatfield);
# define ordered_set tree<int, null_type,less<int>, rb_tree_tag,tree_order_statistics_node_update>
// find_by_order() - Returns an iterator to the k-th largest element (counting from zero)
// order_of_key() - The number of items in a set that are strictly smaller than our item
// greater instead of less for descending order
// less_equal works as ordered multiset
// we can use pair<int,int> instead of int for pair of orderd set
// for multiset st.lower_bound(x) works as upper bound and st.upper_bound(x) works as lower bound
inline void file() {
#ifndef ONLINE_JUDGE
freopen("input.txt", "r", stdin);
freopen("output.txt", "w", stdout);
#endif // ONLINE_JUDGE
}
//----------------------------------------------------------------------------------------------------------------------------------|
// DEBUGGER //
//----------------------------------------------------------------------------------------------------------------------------------|
template < typename F, typename S > ostream& operator << ( ostream& os, const pair< F, S > & p ) { return os << "(" << p.first << ", " << p.second << ")"; }
template < typename T > ostream &operator << ( ostream & os, const vector< T > &v ) { os << "{"; for(auto it = v.begin(); it != v.end(); ++it) { if( it != v.begin() ) os << ", "; os << *it; } return os << "}"; }
template < typename T > ostream &operator << ( ostream & os, const set< T > &v ) { os << "["; for(auto it = v.begin(); it != v.end(); ++it) { if( it != v.begin() ) os << ", "; os << *it; } return os << "]"; }
template < typename T > ostream &operator << ( ostream & os, const multiset< T > &v ) { os << "["; for(auto it = v.begin(); it != v.end(); ++it) { if( it != v.begin() ) os << ", "; os << *it; } return os << "]"; }
template < typename F, typename S > ostream &operator << ( ostream & os, const map< F, S > &v ) { os << "["; for(auto it = v.begin(); it != v.end(); ++it) { if( it != v.begin() ) os << ", "; os << it -> first << " = " << it -> second ; } return os << "]"; }
#define dbg(args...) do {cerr << #args << " : "; iamarman(args); } while(0)
void iamarman () { cerr << endl; }
template <typename T> void iamarman( T a[], int n ) { for(int i = 0; i < n; ++i) cerr << a[i] << ' '; cerr << endl; }
template <typename T, typename ... hello> void iamarman( T arg, const hello &... rest) { cerr << arg << ' '; iamarman(rest...); }
//--------------------------------------------------------------------------------------------------------------------------------------|
///// FUNCTIONS /////
ll bigmod(ll base,ll power){ ll res=1; ll p=base%mod; while(power>0) { if(power%2==1) { res=((res%mod)*(p%mod))%mod; } power/=2; p=((p%mod)*(p%mod))%mod; } return res; }
ll inversemod(ll base) { return bigmod(base,mod-2); }
ll poww(ull a,ull b) { ull ans=1; if(!b) return 1; while(b>1) { if(b&1) { ans=ans*a%mod; } a=a*a%mod; b/=2; }return a*ans%mod; }
ll gcd(ll a,ll b) { ll rem; while(b%a!=0) { rem=b%a; b=a; a=rem; } return a; }
ll sqrtt(ll a){ long long x = sqrt(a) + 2; while (x * x > a) x--; return x;}
ll sqrt(ll n) {ll low=0,high=1e10; while(high-low>1){ ll mid=low+(high-low)/2; if(mid*mid<=n) low=mid; else high=mid; }return low; }
long double sqrtd(long double n){ long double low=0,high=n,mid; for(int i=0;i<100;i++) { mid=(low+high)/2; if(mid*mid<=n) low=mid; else high=mid;} return low;}
mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
inline ll getrandom(ll a,ll b) { return uniform_int_distribution<ll>(a,b)(rng); }
int dx[]={-1, 1 , 0 , 0 , -1 ,-1, 1, 1};
int dy[]={ 0, 0 ,-1 , 1 , -1 , 1,-1, 1};
// up = { -1,0 } , down = { 1,0 } , right = { 0,1 } , left = { 0,-1 }
// up-right = { -1,1 } , up-left = { -1,-1 } , down-right = { 1,1 } , down-left = { 1,-1 }
/// ____________CODE STARTS FROM HERE____________ ///
struct Node {
int child[2];
int cnt;
int anyIndex; // stores an example index of a number passing through this node
Node(){ child[0]=child[1]=-1; cnt=0; anyIndex=-1; }
};
struct Trie {
vector<Node> t;
int B;
Trie(int bits=31){ B = bits; t.emplace_back(); } // use 31..0 bits by default
void clear(){ t.clear(); t.emplace_back(); }
void insert(int val, int idx){
int cur = 0;
for(int i = B; i >= 0; --i){
int b = (val >> i) & 1;
if(t[cur].child[b] == -1){
t[cur].child[b] = t.size();
t.emplace_back();
}
cur = t[cur].child[b];
t[cur].cnt++;
t[cur].anyIndex = idx; // remember an index that goes through here
}
}
// returns pair<maxxor, index_of_prefix_used_in_trie>
pair<int,int> query_with_index(int x){
int cur = 0;
if(cur == -1) return {0, -1};
int ans = 0;
for(int i = B; i >= 0; --i){
if(cur == -1) break;
int b = (x >> i) & 1;
int want = !b;
if(t[cur].child[want] != -1 && t[t[cur].child[want]].cnt > 0){
ans |= (1<<i);
cur = t[cur].child[want];
} else if(t[cur].child[b] != -1 && t[t[cur].child[b]].cnt > 0){
cur = t[cur].child[b];
} else {
// no path
cur = -1;
break;
}
}
int idx = (cur == -1 ? -1 : t[cur].anyIndex);
return {ans, idx};
}
};
void solve()
{
int n, X;
if(!(cin >> n >> X)) return;
vector<int> vec(n+1,0);
for(int i=1;i<=n;i++){
cin >> vec[i];
vec[i] ^= vec[i-1];
}
Trie trie(29); // 0..29 bits is enough for <=1e9, change to 31 if you prefer
int bestLen = 0;
int bestL = -1, bestLenActual = -1;
auto ok = [&](int len)->bool{
trie.clear();
trie.insert(0, 0); // prefix a[0] at index 0
for(int i = len; i <= n; ++i){
trie.insert(vec[i-len], i-len);
auto pr = trie.query_with_index(vec[i]);
if(pr.first >= X){
// pr.second is the prefix index j used; subarray is j+1 .. i
bestL = pr.second + 1;
bestLenActual = i - pr.second;
return true;
}
}
return false;
};
int lo = 1, hi = n+1;
while(hi - lo > 1){
int mid = lo + (hi - lo) / 2;
if(ok(mid)) lo = mid;
else hi = mid;
}
// re-run to get concrete indices for the maximal length lo
if(ok(lo)){
// print start and actual length (>= lo)
cout << bestL << " " << bestLenActual << "\n";
} else {
// no subarray found at all
cout << -1 << "\n";
}
}
int main()
{
optimise;
//file();
clock_t start= clock();
int t=1;
// cin>>t;
for(int i=1;i<=t;i++)
{
//cout<<"Case "<<i<<": ";
solve();
}
// cerr << "Run Time : " <<((double)(clock() - start) / CLOCKS_PER_SEC)<<el;
}
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