Submission #3716760

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Source Code Expand

#include "bits/stdc++.h"
#include <iostream>
#include <string.h>
#include <stdio.h>
#include <map>
#include <vector>
#include <math.h>
#include <algorithm>
#include <queue>
#include <set>
#include <tuple>
using namespace std;

#define FOR(i,init,a) for(int i=init; i<a; i++)
#define rep(i,a) FOR(i,0,a)
#define rrep(i,a) for(int i=a; i>=0; i--)
#define rep1(i,a) for(int i=1; i<=a; i++)
#define cout1(a) cout << a << endl;
#define cout2(a,b) cout << a << " " << b << endl;
#define cout3(a,b,c) cout << a << " " << b << " " << c << endl;
#define cout4(a,b,c,d) cout << a << " " << b << " " << c << " " << d << endl;
#define mem(a,n) memset( a, n, sizeof(a))
#define all(a) a.begin(),a.end()
#define chmin(a,b) a=min(a,b);
#define chmax(a,b) a=max(a,b);

typedef long long ll;
typedef long double ld;
typedef pair<int,int> pii;
typedef vector<int> V;
typedef vector<V> VV;
typedef vector<VV> VVV;
const int INF = 1e9;
const int MOD = 1e9+7;
const ll LLINF = 1e18;
static const double pi = 3.141592653589793;

int nums[100009];

void win(int cnt){
    cout1(cnt)
    exit(0);
}

int main() {
    cin.tie(0);
    ios::sync_with_stdio(false);
    
    int N,XOR=0;
    cin>>N;
    
    rep(i,N) cin>>nums[i],XOR^=nums[i];
    if(XOR==0) win(0);
    
    int cnt=0;
    rrep(k,32)if(XOR&(1ll<<k)){
        ll x=(1ll<<(k+1))-1;
        int idx=-1;
        rep(i,N){
            if(x==(nums[i]^(nums[i]-1))){
                idx=i;
                break;
            }
        }
        if(idx==-1) win(-1);
        nums[idx]=0,XOR^=x;
        cnt++;
    }
    win(cnt);
}

Submission Info

Judge Result