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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#141245#6516. New but Nostalgic Problemcy1999WA 53ms5720kbC++201.3kb2023-08-17 09:58:122023-08-17 09:58:45

Judging History

你现在查看的是最新测评结果

  • [2023-08-17 09:58:45]
  • 评测
  • 测评结果:WA
  • 用时:53ms
  • 内存:5720kb
  • [2023-08-17 09:58:12]
  • 提交

answer

#include<bits/stdc++.h>

using namespace std;

const int N=1000010;

int son[N][26],idx,cnt[N],sfx[N][27];
int n,k;

void ins(const string &s){
	int p=0;
	for(int i=0; i<s.size(); i++){
		cnt[p]++;
		if(!son[p][s[i]-'a']) son[p][s[i]-'a']=++idx;
		p=son[p][s[i]-'a'];
	}
	cnt[p]++;
}

void init(int p){
	for(int i=25; ~i; i--){
		if(i!=25) sfx[p][i]=sfx[p][i+1];
		if(son[p][i]) sfx[p][i]+=(cnt[son[p][i]]>0?1:0);
		if(son[p][i]) init(son[p][i]);
	}
}

string dfs(int p,int k){
	if(k<=sfx[p][0]) return "";
	int sum=0;
	string ret;
	for(int i=0; i<26; i++){
		if(!son[p][i]) continue;
		if(sum+sfx[p][i+1]+cnt[son[p][i]]>=k){
			return dfs(son[p][i],k-sum-sfx[p][i+1])+(char)('a'+i);
		}
		sum+=cnt[son[p][i]];
	}
	return "";
}

void solve(){
	for(int i=0; i<=idx+6; i++){
		for(int j=0; j<26; j++) son[i][j]=0,sfx[i][j]=0;
		cnt[i]=0;
	}
	idx=0;
	cin>>n>>k;
	for(int i=1; i<=n; i++){
		string t;
		cin>>t;
		ins(t);
	}
	
	init(0);
	string ans=dfs(0,k);
	if(!ans.size()){
		cout<<"EMPTY\n";
		return ;
	}
	
	reverse(ans.begin(),ans.end());
	cout<<ans<<'\n';
}

int main(){
	
	ios::sync_with_stdio(false);
	cin.tie(nullptr);
	
	int T;
	cin>>T;
	while(T--) solve();
	
	return 0;
}

/*

2
5 3
gdcpc
gdcpcpcp
suasua
suas
sususua
3 3
a
b
c

1
8 4
ab
ac
bb
bc
cc
cb
db
dc


*/

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 100
Accepted
time: 1ms
memory: 5568kb

input:

2
5 3
gdcpc
gdcpcpcp
suasua
suas
sususua
3 3
a
b
c

output:

gdcpc
EMPTY

result:

ok 2 lines

Test #2:

score: 0
Accepted
time: 46ms
memory: 5588kb

input:

20000
5 3
apveofpr
irdbqk
rnionnjjrk
wrpihlsw
ofylfsriof
5 4
iiltghqg
kybhogptqf
jfnmqxzrdq
rpztcluq
tzmnrcjae
5 5
ysp
vujmkkcutl
ksawqeiiaf
waukilaq
wmlsutlued
5 3
pikybt
yiqmqvtjeq
tyrsoihf
vnvjrxpus
cuubpacubb
5 2
rihuvikhg
twrsuoervz
ukiekoohw
eysqgndpf
sxswpeqtaf
5 5
vxzhicbp
nvtdbgqal
jilppvpt...

output:

EMPTY
EMPTY
w
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
o
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
t
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
w
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPT...

result:

ok 20000 lines

Test #3:

score: 0
Accepted
time: 45ms
memory: 5720kb

input:

1000
10 9
wkpbdhbivgksnwvnqnynzrmhowmpbbtswjydwidifwuquenplmozlqnkxqefckyzcughrdbturdzsxrcggpzrtrvlewigox
qbxgxomnfarjtvfbxbabtpmhnuwvbxfpwpkjuzjsehofemfzxglvvthzgkzukwmlyfhajchvphdjfqmfubwwpdtdbjpfvk
qrsovcdbphsndcmjwxjhmktwvgakzqewnoymumlawlmmgjmbpivccldrrfgspjypwosdqgpyqnxhaukwycqntuxglbdwf
fbdtn...

output:

q
EMPTY
EMPTY
EMPTY
h
EMPTY
EMPTY
EMPTY
h
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
v
b
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
t
EMPTY
EMPTY
e
EMPTY
b
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
b
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
v
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPT...

result:

ok 1000 lines

Test #4:

score: -100
Wrong Answer
time: 53ms
memory: 5604kb

input:

25000
10 8
phl
vwel
ufme
dtsf
con
giby
xlma
dhke
zjir
itws
9 5
qtgd
wcqj
ixmz
swv
myxo
eqq
yxiq
uvb
spbw
10 7
xrkp
ze
smt
nq
ijhw
lmxf
kcgs
hi
qwmq
hilw
8 7
rlf
taaq
hmdu
thex
dbb
spcp
awyn
khdu
10 10
voxx
tqv
ehtx
xctk
zamh
zua
rbyg
bmeh
wmiv
cmw
9 6
bzq
ayz
cdna
myi
rdeu
gtdo
ycy
sjec
ystp
9 4
tix...

output:

EMPTY
EMPTY
EMPTY
EMPTY
z
EMPTY
EMPTY
s
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
y
EMPTY
EMPTY
a
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
m
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
g
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
j
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
j
EMPTY
t
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
...

result:

wrong answer 3236th lines differ - expected: 'pfv', found: 'p'