Submission #482266

#	Time	Username	Problem	Language	Result	Execution time	Memory
482266		urosk	XOR (IZhO12_xor)	C++14	100 / 100	142 ms	46344 KiB

xor

// __builtin_popcount(x) broj bitova
// __builtin_popcountll(x) long long
#define here cerr<<"---------------------------\n"
#include "bits/stdc++.h"
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>
#define ld double
#define ll long long
#define ull unsigned long long
#define llinf 100000000000000000LL // 10^17
#define iinf 2000000000 // 2*10^9
#define pb push_back
#define popb pop_back
#define fi first
#define sc second
#define endl '\n'
#define pii pair<int,int>
#define pll pair<ll,ll>
#define pld pair<ld,ld>
#define sz(a) int(a.size())
#define all(a) a.begin(),a.end()
#define rall(a) a.begin(),a.end(),greater<int>()
#define getunique(v) {sort(all(v)); v.erase(unique(all(v)), v.end());}
#define pi 3.14159265358979323846
using namespace std;
using namespace __gnu_pbds;

typedef tree<int,null_type,less<int>,rb_tree_tag,tree_order_statistics_node_update> ordered_set;

void setIO(string inoutname)
{
	freopen((inoutname+".in").c_str(),"r",stdin);
    	freopen((inoutname+".out").c_str(),"w",stdout);
}

#define maxn 250005
#define maxx 5000005
#define lg 31
ll n,x;
ll a[maxn];
ll t[maxx][2];
ll col[maxx];
ll id = 1;
void add(ll x,ll z){
    ll i = 0;
    for(ll j = lg;j>=0;j--){
        ll b = (1<<j)&x;
        if(b>0) b = 1;
        if(t[i][b]==0){
            t[i][b] = id;
            col[id] = z;
            id++;
        }
        i = t[i][b];
        col[i] = min(col[i],z);
    }
}
ll reshi(ll id){
    ll y = a[id];
    ll i = 0;
    ll ans = llinf;
    ll sum = 0;
    for(ll j = lg;j>=0;j--){
        ll b = (1<<j)&y;
        ll c = (1<<j)&x;
        if(b>0) b = 1;
        if(c>0) c = 1;
        if(c){
            if(t[i][!b]==0) break;
            i = t[i][!b];
        }else{
            if(t[i][!b]){
                ans = min({ans,col[t[i][!b]],col[t[i][!b]]});
            }
            if(t[i][b]==0) break;
            i = t[i][b];
        }
    }
    if(ans==llinf) return -1;
    return ans;
}
void tc(){
	//ios_base::sync_with_stdio(false);cerr.tie(0);cout.tie(0);cin.tie(0);;
    cin >> n >> x;
    for(ll i = 1;i<=n;i++){
        cin >> a[i];
        a[i] = a[i]^a[i-1];
    }
    ll len = -1;
    ll j = -1;
    x--;
    for(ll i = 1;i<=n;i++){
        if(a[i]>x){
            len = i;
            j = 1;
            add(a[i],i);
            //cerr<<1<< " "<<i<<endl;
            continue;
        }
        ll j2 = reshi(i)+1;
        //cerr<<j2<< " "<<i<<endl;
        if(j2==0){
            add(a[i],i);
            continue;
        }
        ll len2 = i-j2+1;
        if((a[i]^a[j2-1])>=x&&len2>len){
            swap(len,len2);
            swap(j,j2);
        }
        add(a[i],i);
    }
    cout<<j<< " "<<len<<endl;
}
int main(){
	ios_base::sync_with_stdio(false);cerr.tie(0);cout.tie(0);cin.tie(0);
	//setIO("lol");
	int t; t = 1;
	while(t--){
		tc();
	}
	return 0;
}
/*
4 6
6 1 2 4
out: 2 3
*/

Compilation message (stderr)

xor.cpp: In function 'long long int reshi(long long int)':
xor.cpp:62:8: warning: unused variable 'sum' [-Wunused-variable]
   62 |     ll sum = 0;
      |        ^~~
xor.cpp: In function 'void setIO(std::string)':
xor.cpp:32:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   32 |  freopen((inoutname+".in").c_str(),"r",stdin);
      |  ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
xor.cpp:33:13: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   33 |      freopen((inoutname+".out").c_str(),"w",stdout);
      |      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 100 / 100