Submission #342499

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
342499	2021-01-02T09:17:46 Z	nandonathaniel	XOR (IZhO12_xor)	C++14	100 / 100	591 ms	98556 KB

xor

#include<bits/stdc++.h>
using namespace std;
const int LOG=30,RAND=8e6+5;
int child[2][RAND],anak[RAND],parent[RAND];
unordered_map<int,int> sudah,ujung;
int s,ret,n,k,x,i;
 
void ngisi(int tmp,int pos){
	if(pos==-1)return;
	if(child[0][tmp]!=-1 && child[1][tmp]!=-1){
		anak[tmp]=min(anak[child[0][tmp]],anak[child[1][tmp]]);
	}
	else if(child[1][tmp]!=-1){
		anak[tmp]=anak[child[1][tmp]];
	}
	else if(child[0][tmp]!=-1){
		anak[tmp]=anak[child[0][tmp]];
	}
	ngisi(parent[tmp],pos-1);
}
 
void insert(int tmp,int pos){
	if(pos==-1){
		sudah[s]=tmp;
		return;
	}
	int now=s&(1<<pos);
	if(now>0)now=1;
	if(child[now][tmp]==-1){
		ret++;
		child[now][tmp]=ret;
		parent[child[now][tmp]]=tmp;
		anak[child[now][tmp]]=i+1;
	}
	insert(child[now][tmp],pos-1);
}

int search(int tmp,int pos){
	if(child[0][tmp]==-1 && child[1][tmp]==-1)return RAND;
	int bitk=k&(1<<pos),bits=s&(1<<pos);
	if(bitk>0)bitk=1;
	if(bits>0)bits=1;
	int res=RAND;
	if(bitk==1){
		if(bits==1){
			if(child[0][tmp]!=-1){
				res=min(res,search(child[0][tmp],pos-1));
			}
		}
		else{
			if(child[1][tmp]!=-1){
				res=min(res,search(child[1][tmp],pos-1));
			}
		}
	}
	else{
		if(bits==0){
			if(child[0][tmp]!=-1){
				res=min(res,search(child[0][tmp],pos-1));
			}
			if(child[1][tmp]!=-1){
				res=min(res,anak[child[1][tmp]]);
			}
		}
		else{
			if(child[1][tmp]!=-1){
				res=min(res,search(child[1][tmp],pos-1));
			}
			if(child[0][tmp]!=-1){
				res=min(res,anak[child[0][tmp]]);
			}
		}
	}
	return res;
}

int main(){
	memset(child,-1,sizeof(child));
	scanf("%d%d",&n,&k);
	anak[s]=1;
	insert(0,0);
	ujung[s]=1;
	int pjg=-1,awal;
	for(i=1;i<=n;i++){
		scanf("%d",&x);
		s^=x;
		int L=search(0,LOG-1);
		if(ujung.count(k^s))L=min(L,ujung[k^s]);
		if(L>=1 && L<=i){
			if(i-L+1>pjg){
				pjg=i-L+1;
				awal=L;
			}
		}
		if(!sudah.count(s)){
			insert(0,LOG-1);
		}
		ngisi(sudah[s],LOG-1);
		if(!ujung.count(s))ujung[s]=i+1;
	}
	printf("%d %d\n",awal,pjg);
	return 0;
}

Compilation message

xor.cpp: In function 'int main()':
xor.cpp:79:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   79 |  scanf("%d%d",&n,&k);
      |  ~~~~~^~~~~~~~~~~~~~
xor.cpp:85:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   85 |   scanf("%d",&x);
      |   ~~~~~^~~~~~~~~

Subtask #1

100.0 / 100.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	32 ms	62956 KB	Output is correct
2	Correct	33 ms	62956 KB	Output is correct
3	Correct	32 ms	62956 KB	Output is correct
4	Correct	33 ms	63084 KB	Output is correct
5	Correct	48 ms	65132 KB	Output is correct
6	Correct	52 ms	65260 KB	Output is correct
7	Correct	53 ms	65260 KB	Output is correct
8	Correct	57 ms	65516 KB	Output is correct
9	Correct	209 ms	78644 KB	Output is correct
10	Correct	223 ms	78660 KB	Output is correct
11	Correct	209 ms	78692 KB	Output is correct
12	Correct	201 ms	78516 KB	Output is correct
13	Correct	209 ms	78516 KB	Output is correct
14	Correct	208 ms	78900 KB	Output is correct
15	Correct	210 ms	78516 KB	Output is correct
16	Correct	200 ms	78516 KB	Output is correct
17	Correct	579 ms	98500 KB	Output is correct
18	Correct	572 ms	98428 KB	Output is correct
19	Correct	591 ms	98556 KB	Output is correct
20	Correct	565 ms	98428 KB	Output is correct