제출 #362488

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
362488		keta_tsimakuridze	XOR Sum (info1cup17_xorsum)	C++14	45 / 100	1613 ms	19016 KiB

xorsum

#include<bits/stdc++.h>
#define f first
#define s second
using namespace std;
const int N=1e6+5;
int a[N],s[N],n,cnt,c[2],ans,cur,pos[N],f[2][N],pwr[35];
main(){
	ios_base::sync_with_stdio(false),cin.tie(0),cout.tie(0);
	cin>>n;
	for(int i=0;i<=32;i++)
	pwr[i]=1<<i;
	for(int k=1;k<=n;k++){
		cin>>a[k]; pos[k]=k; 
		cnt+=c[(a[k]&1)^1];
		c[a[k]&1]++;
		s[k]=a[k]&1;
	}
	if(cnt%2) ans=1;
	int i=0;
		c[1]=c[0]=0;
	for(int k=1;k<=n;k++){
		int b = (pwr[i]&a[pos[k]]);
		b=min(b,1);
		c[b]++;
		f[b][c[b]]=pos[k];
	}
	cur=0;
	for(int j=0;j<=1;j++){
		for(int k=1;k<=c[j];k++){
			cur++;
			pos[cur]=f[j][k];
		}
	}
	
	for(int i=1;i<=30;i++){
	c[1]=c[0]=0;
	for(int k=1;k<=n;k++){
		int b = ((pwr[i])&a[pos[k]]);
		b=min(b,1);
		c[b]++;
		f[b][c[b]]=pos[k];
	}
	cur=0;
	for(int j=0;j<=1;j++){
		for(int k=1;k<=c[j];k++){
			cur++;
			pos[cur]=f[j][k];
		}
	}
		for(int k=1;k<=n;k++)
		s[k]+=a[k]&pwr[i];
		cnt=0;
		int l=n,r=n,l1=n,r1=n;
		for(int k=1;k<=n;k++){
		         while(r && s[pos[r]] + s[pos[k]] >= (pwr[i+1]) ) r--;
		         while(l && s[pos[l]] + s[pos[k]] >= pwr[i]) l--;
		         cnt += r-l; cnt %=4;  
		         while( l1&&s[pos[l1]] + s[pos[k]] >=(pwr[i+1]+pwr[i]) ) l1--;
		         cnt+=n-l1; cnt%=4;
		}
		
		int c1=0;
		for(int k=1;k<=n;k++){
		           if((2*a[k])&pwr[i]) c1++;
		}
        c1%=4;
		if((c1+(cnt-c1+4)/2)%2==1) ans+=pwr[i];
		
	}
	cout<<ans;
}

컴파일 시 표준 에러 (stderr) 메시지

xorsum.cpp:7:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
    7 | main(){
      |      ^
xorsum.cpp: In function 'int main()':
xorsum.cpp:53:20: warning: unused variable 'r1' [-Wunused-variable]
   53 |   int l=n,r=n,l1=n,r1=n;
      |                    ^~

• Subtask 1: 7 / 7
• Subtask 2: 0 / 11
• Subtask 3: 0 / 21
• Subtask 4: 38 / 38
• Subtask 5: 0 / 23