Submission #343489

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
343489	2021-01-04T01:27:23 Z	nandonathaniel	XOR (IZhO12_xor)	C++14	100 / 100	573 ms	98180 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,LOG-1);
	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	32 ms	62956 KB	Output is correct
3	Correct	32 ms	62956 KB	Output is correct
4	Correct	35 ms	63212 KB	Output is correct
5	Correct	49 ms	65152 KB	Output is correct
6	Correct	54 ms	65132 KB	Output is correct
7	Correct	53 ms	65260 KB	Output is correct
8	Correct	57 ms	65388 KB	Output is correct
9	Correct	204 ms	78644 KB	Output is correct
10	Correct	197 ms	78644 KB	Output is correct
11	Correct	198 ms	78544 KB	Output is correct
12	Correct	227 ms	78516 KB	Output is correct
13	Correct	218 ms	78644 KB	Output is correct
14	Correct	201 ms	78772 KB	Output is correct
15	Correct	206 ms	78516 KB	Output is correct
16	Correct	202 ms	78516 KB	Output is correct
17	Correct	573 ms	98180 KB	Output is correct
18	Correct	565 ms	97968 KB	Output is correct
19	Correct	567 ms	98044 KB	Output is correct
20	Correct	558 ms	98044 KB	Output is correct