Submission #875892

#	Time	Username	Problem	Language	Result	Execution time	Memory
875892		derar_alhamsh	XOR (IZhO12_xor)	C++14	0 / 100	1 ms	348 KiB

xor

#include <bits/stdc++.h>
#define ll long long
#define ld long double
#define mod 1000000007
#define mxe(v)   *max_element(v.begin(), v.end())
#define all(v)   v.begin(), v.end()
#define allr(v) v.rbegin(),v.rend()
#define F first
#define S second
#define pi pair<ll,ll>
#define derar ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define yes cout<<"YES"<<endl;
#define no cout<<"NO"<<endl;
using namespace std;
const int N=400200;
const double PI=3.1415926535897932384626433;
const double eps = 1e-9;
string getString()
{
    char c[(int)2e6];
    //scanf(" %c",&a[i]);
    scanf("%s", c);
    return c;
    //string x = getString();
}
///printf("%d\n",);
///scanf("%d",&);
///cout.precision(10);
///puts("")string
const int LOG = 32;

struct trienode {
    trienode *child[2];
    ll cnt, end;

    trienode() {
        memset(child, 0, sizeof child);
        cnt = end = 0;
    }

    void add(int i, bitset<LOG> &bt) {
        int cur = bt[i];
        if (child[cur] == 0) child[cur] = new trienode();
        child[cur]->cnt++;
        if (i == 0) {
            child[cur]->end++;
            return;
        }
        child[cur]->add(i - 1, bt);
    }

    void add(ll num) {
        cnt++;
        bitset<LOG> bt(num);
        add(LOG - 1, bt);
    }
    void erase(int i, bitset<LOG> &bt) {
        int cur = bt[i];
        child[cur]->cnt--;
        if (i == 0) {
            child[cur]->end--;
            if (!child[cur]->cnt) {
                delete child[cur];
                child[cur] = 0;
            }
            return;
        }
        child[cur]->erase(i - 1, bt);
        if (!child[cur]->cnt) {
            delete child[cur];
            child[cur] = 0;
        }
    }

    void erase(ll num) {
        bitset<LOG> bt(num);
        if (!find(num))return;
        cnt--;
        erase(LOG - 1, bt);
    }
    bool find(int i, bitset<LOG> &bt) {
        int cur = bt[i];
        if (child[cur] == 0)return 0;
        if (i == 0) {
            return child[cur]->end > 0;
        }
        return child[cur]->find(i - 1, bt);
    }

    bool find(ll num) {
        bitset<LOG> bt(num);
        return find(LOG - 1, bt);
    }
    ll GetIndex(int i, bitset<LOG> &bt) {
        int cur = bt[i];
        if (child[cur] == 0) return 0;
        int less = 0;
        if (bt[i] && child[0] != 0)less += child[0]->cnt;
        if (i == 0)return less;
        return less + child[cur]->GetIndex(i - 1, bt);
    }

    ll GetIndex(ll num) {
        bitset<LOG> bt(num);
        if (!find(num))return -1;
        return GetIndex(LOG - 1, bt);
    }
    ll GetMaxXor(int i, bitset<LOG> &bt) {
        int cur = bt[i];
        if (i == 0) {
            if (child[!cur])return (1ll << i);
            else return 0;
        }
        if (child[!cur])return (1ll << i) + child[!cur]->GetMaxXor(i - 1, bt);
        else if (child[cur])return child[cur]->GetMaxXor(i - 1, bt);
        else return 0;
    }
    ll GetMaxXor(ll num) {
        bitset<LOG> bt(num);
        return GetMaxXor(LOG - 1, bt);
    }
    ll low(int i, bitset<LOG> &bt,bitset<LOG> &bt1)
    {
        int cur = bt[i],less = 0;
        if(i==-1)
            return 0;
        if (bt[i]==1 && bt1[i]==1)
        {
            if(child[1])
                 less+=child[1]->cnt;
            if(child[0])
                return less+=child[0]->low(i-1,bt,bt1);
            return less;
        }
        else if(bt[i]==0 && bt1[i]==0)
        {
            if(child[0])
                return child[0]->low(i-1,bt,bt1);
            return 0;
        }
        else if(bt[i]==1 && bt1[i]==0)
        {
            if(child[1])
                return less+=child[1]->low(i-1,bt,bt1);
            return less;
        }
        else if(bt[i]==0 && bt1[i]==1)
        {
            if(child[0])
                less+=child[0]->cnt;
            if(child[1])
                return  less+=child[1]->low(i-1,bt,bt1);
            return less;
        }
    }
    ll low(ll num,ll k) {
        bitset<LOG> bt(num);
        bitset<LOG> bt1(k);
        return low(LOG - 1, bt,bt1);
    }
    ll count(int i, bitset<LOG> &bt) {
        int cur = bt[i];
        if (child[cur] == 0)return 0;
        if (i == 0) {
            return child[cur]->cnt;
        }
        return child[cur]->count(i - 1, bt);
    }
    ll count(ll num) {
        bitset<LOG> bt(num);
        return count(LOG - 1, bt);
    }
    void clear() {
        for (int i = 0; i < 2; i++)
            if (child[i])
                child[i]->clear(), delete child[i], child[i] = 0;
    }
};
int main()
{
    derar
    int t=1;
    //cin>>t;
    while(t--)
    {
        ll n,k;
        cin>>n>>k;
        int a[n];
        trienode* root=new trienode();
        for(int i=0;i<n;i++)
            cin>>a[i];
        ll pre=0,ans=n+1,count=1,c=0;
        root->add(0);
        for(int i=n-1; i>0; i--)
        {
            pre^=a[i];
            c+=root->low(pre,k);
            if(c<count)
            {
                ans=i+1;
            }
            count+=n-i+1;
            root->add(pre);
        }
        cout<<ans<<" ";
        int ma=a[ans-1],x=ans;
        for(int i=ans;i<n;i++)
        {
            ma^=a[i];
            if(ma>=k)
                x=i;
        }
        cout<<x;
    }
}

Compilation message (stderr)

xor.cpp: In member function 'long long int trienode::low(int, std::bitset<32>&, std::bitset<32>&)':
xor.cpp:124:13: warning: unused variable 'cur' [-Wunused-variable]
  124 |         int cur = bt[i],less = 0;
      |             ^~~
xor.cpp: In function 'std::string getString()':
xor.cpp:22:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   22 |     scanf("%s", c);
      |     ~~~~~^~~~~~~~~
xor.cpp: In member function 'long long int trienode::low(int, std::bitset<32>&, std::bitset<32>&)':
xor.cpp:155:5: warning: control reaches end of non-void function [-Wreturn-type]
  155 |     }
      |     ^

• Subtask 1: 0 / 100