Submission #523524

#	Time	Username	Problem	Language	Result	Execution time	Memory
523524		lukameladze	XOR (IZhO12_xor)	C++14	0 / 100	2015 ms	172084 KiB

xor

# include <bits/stdc++.h>
#define f first
#define s second
#define pb push_back
#define int long long
using namespace std;
const int N = 3e5 + 5;
int n,x,a[N],pref,idx,sf[N],posri,le,mx,sz,idd,val;
map <int, int> fix[31];
void go(int lee , int rii ){
	sz = rii - lee + 1;
	if (sz >= mx) {
		le = lee;
		mx = sz; 
	}
}
main() {
    cin>>n>>x;
    for (int i = 1; i <= n; i++) {
        cin>>a[i];
    }
    for (int i = 30; i >= 0; i--) {
        if ((1LL<<i)&x) {
            idx = i;
            break;
        } 
        pref += (1<<i);
    }
    
    for (int j = idx; j >= 0; j--) {
       fix[j][0] = n + 1;
    }
    for(int i = n; i >= 1; i--) {
       // if (i == 1) cout<<le<<"   "<<mx<<endl;
        sf[i] = sf[i + 1] ^ a[i];
        //if (i == 2) cout<<sf[i]<<" "<<(int)(pref&sf[i])<<endl;
        if ((pref&sf[i])) {
            le = i;
            mx = n - i + 1;
            if (!idd) idd = i;
            int val = 0;
            for (int j = idx; j >= 0; j--) {
                if ((1LL<<j)&sf[i]) val += (1LL<<j);
                fix[j][val] = max(fix[j][val],i);
            }
            continue;
        }
        posri = idd - 1;
        sz = posri - i + 1;
        if (sz >= mx) {
            le = i;
            mx = sz;
        }
        int haveto = 0;
        for (int j = idx; j >= 0; j--) {
            if ((1<<j)&x) {
                if (!((1LL<<j)&sf[i])) haveto += (1LL<<j); 
                continue;
            }
            if ((1<<j)&sf[i]) {
                if (fix[j][haveto]) go(i, fix[j][haveto] - 1);
                haveto += (1LL<<j);
                continue;
            }
            if (fix[j][haveto + (1LL<<j)]) go(i, fix[j][haveto + (1LL<<j)] - 1);
        }
        if (fix[0][haveto]) {
            go(i,fix[0][haveto] - 1);
        }
        int val = 0;
        for (int j = idx; j >= 0; j--) {
            if ((1LL<<j)&sf[i]) val += (1LL<<j);
            fix[j][val] = max(fix[j][val],i);
        }
    }
    cout<<le<<" "<<mx<<endl;
}

Compilation message (stderr)

xor.cpp:17:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   17 | main() {
      | ^~~~

• Subtask 1: 0 / 100