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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#557239#8668. 回文路径lichenghan100 ✓35ms7916kbC++141.8kb2024-09-11 08:21:172024-09-11 08:21:18

Judging History

你现在查看的是最新测评结果

  • [2024-09-11 08:21:18]
  • 评测
  • 测评结果:100
  • 用时:35ms
  • 内存:7916kb
  • [2024-09-11 08:21:17]
  • 提交

answer

#include <bits/stdc++.h>
#define hash unsigned long long
using namespace std;
const int N=1e5+10;
hash bas=5'281'975'703'421'989'899ll;
hash pw[N];
void init_bas(){
	pw[0]=1;
	for(int i=1;i<N;i++){
		pw[i]=pw[i-1]*bas;
	}
}
int n;
char a[N],b[N];
hash pa[N],pb[N],sa[N],sb[N];
void init_hash(){
	init_bas();
	for(int i=1;i<=n;i++) pa[i]=pa[i-1]*bas+a[i],pb[i]=pb[i-1]*bas+b[i];
	for(int i=n;i>=1;i--) sa[i]=sa[i+1]*bas+a[i],sb[i]=sb[i+1]*bas+b[i];
}
int ap(int l,int r){ return pa[r]-pa[l-1]*pw[r-l+1]; }
int bp(int l,int r){ return pb[r]-pb[l-1]*pw[r-l+1]; }
int as(int l,int r){ return sa[l]-sa[r+1]*pw[r-l+1]; }
int bs(int l,int r){ return sb[l]-sb[r+1]*pw[r-l+1]; }
int solve(){
	init_hash();
	auto maxok=[&](int l,int r,auto chk){
		int mid,ans=-1;
		while(l<=r) {
			mid=(l+r)>>1;
			if(chk(mid)){
				ans=mid;
				l=mid+1;
			}else{
				r=mid-1;
			}
		}
		return ans;
	};
	int ans=0;
	for(int i=1;i<=n;i++){
		// at a[i]
		int alen=maxok(0,min(i-1,n-i),[&](int x){ return ap(i-x,i-1)==as(i+1,i+x); });
		int blen=maxok(0,min(i-1-alen,n-i-alen+1),[&](int x){ return ap(i-alen-x,i-alen-1)==bs(i+alen,i+alen+x-1); });
		ans=max(ans,2*(alen+blen)+1);
	}
	for(int i=1;i<n;i++) if(a[i]==a[i+1]) {
		// at a[i]-a[i+1]
		int alen=maxok(0,min(i,n-i),[&](int x){ return ap(i-x+1,i)==as(i+1,i+x); });
		int blen=maxok(0,min(i-alen,n-i-alen+1),[&](int x){ return ap(i-alen-x+1,i-alen)==bs(i+alen,i+alen+x-1); });
		ans=max(ans,2*(alen+blen));
	}
	for(int i=1;i<=n;i++){
		// at a[i]-b[i]
		int len=maxok(0,max(i,n-i+1),[&](int x){ return ap(i-x+1,i)==bs(i,i+x-1); });
		ans=max(ans,2*len);
	}
	return ans;
}
int main(){
	scanf("%d%s%s",&n,a+1,b+1);
	int ans=solve();
	for(int i=1;i<=n;i++) swap(a[i],b[i]);
	reverse(a+1,a+n+1);
	reverse(b+1,b+n+1);
	ans=max(ans,solve());
	cout<<ans<<endl;
}

Details

Tip: Click on the bar to expand more detailed information

Subtask #1:

score: 30
Accepted

Test #1:

score: 30
Accepted
time: 1ms
memory: 6404kb

input:

1000
mfmlkrasfiudkzrjzyrlbpitvzfrlmjdzsurtdcmnqpsyfgobbstvplqylvciloomaljyssxtrrccywyirfvlcnchwkfwbdaoxzpfpvlruptganojnfxmnlqetptmlmoyluxvaipghtlaszoozscdmjomobyzboqqmvqjpbfjsoczhkwrlcauzjceqikbaeuiqahnldpqmohfjfzgkbfdbqnoxispkejvpncwsyelebqumapgbfdrjvuaxaphnkciwzkruijmanwslkwosgyfhwbnsthhtxrhrzlgtt...

output:

6

result:

ok single line: '6'

Test #2:

score: 30
Accepted
time: 1ms
memory: 6468kb

input:

1000
wvitzoxwlmhexjuqvoxksetoupgkhattucdzfevqorkdlsymjuvhobdrjsodtipwpfhipsdnyvqtsbbasrrvyybijzmpwseckztnpnkqswgkaeivflhwevhxcchjsnelqcixexkntwiuolsditpdwypgerzijziyrgqkwuucnqaehuwkpyrmwewjitvsaebyytznbtnkulnepceeloyjpfhcdpqfqhvzsmkcynjwztmkbnqaxnikfuiutocahdfbvsgdskgwqmzizzjlbqxnngftdohetabpjzpqzyc...

output:

7

result:

ok single line: '7'

Test #3:

score: 30
Accepted
time: 0ms
memory: 6560kb

input:

1000
abababaabaababbbbabbbbabbbbbbabbbaabbbaababaabaabbabbbbaabbaabaaaabbaaabbbbaaaaaabbbbababaababbaabbbbbbbbabbaababbbbabbaabbbabaaababbaababbbaabaabaababaaababbaaaababbbbbaaabbaabbaaabbaaaaabaaaaaabbbbbaaabbbbbaabbbbababaabaabbbbaaaaababaaaababbbbbbaababbbaaaababaabaabaabaaaaaabbabbabbbbbbbbbbabb...

output:

28

result:

ok single line: '28'

Test #4:

score: 30
Accepted
time: 0ms
memory: 4404kb

input:

1000
ababbababababbaababaaabaabaababbaabbbabaababbaaababbabbbbaabbababbbababbabababbaabbbaababbabaaaaabbbbbaaaaaaaaabbbbaabbbaabbababaaabababbaaaabababbbaabaabbabbaabaaaaaaabaaabaaababaaaababbaaabaabbbbbbaabbabaaabaabbbbabbababbbaaaaabbabbaabbaabbaabaaabaaabbbbbaabaaaaaababbbbbabbbabbbabababbbbbabaa...

output:

27

result:

ok single line: '27'

Test #5:

score: 30
Accepted
time: 1ms
memory: 6148kb

input:

1000
abbabbababbabbababbababbabbababbabbababbababbabbababbababbabbababbabbababbababbabbababbabbababbababbabbababbababbabbababbabbababbababbabbababbababbabbababbabbababbababbabbababbabbababbababbabbababbababbabbababbabbababbababbabbababbabbababbababbabbababbababbabbababbabbababbababbabbababbababbabba...

output:

987

result:

ok single line: '987'

Test #6:

score: 30
Accepted
time: 1ms
memory: 4660kb

input:

1000
aaaaaaababbabbabaabaaaaababaaaaaabaabaaaabaaaaaaabbbabaabbaaabaaaaaaabaaaaaaaabaaabbaababaaaaaaaaabbaabbabbaaaaabaaaaaaaabbaaabaaaaaaaaaaabaabbbbbaaaabaaaaaaaaabbbaaaaabaaabaaaaaaaaaaaaaababaaaaabbaabbaaaabaabaaaababaaaaaababaaaaabaaaaaaabaaaababaaaabbaaaabaaaaabaaaaaaaabaaaaaaabaaaaaaaaaaaabaa...

output:

45

result:

ok single line: '45'

Test #7:

score: 30
Accepted
time: 1ms
memory: 6268kb

input:

1000
aaaaaabaaaaaaaababaaaaaaababaaaabaabaaaaabaabaaaabbaaaaabaababaaaaaaaaaaabaaaabaaaaaaaaaaaaaaaaaabbaaaaaaababaabaaaabababaaaaabbaaaaaabbababaaabbaaababbaaaabbababaaaaaaaaabbbaaaababaaaaabaaaabbaabaaaaaabbaabaaaaaaaaaaabaaaababbaaaaaaaababbabaaaaaaaaabaaaabaaaaabaaaaaaaaaaaabaaaabaaababaabaabaab...

output:

45

result:

ok single line: '45'

Test #8:

score: 30
Accepted
time: 1ms
memory: 6676kb

input:

1000
aabaaaabaaaabaaabaabbbaabaabbbaaaaaaaaaabaaaaabaababaabaabaaaaaaaaaabbabbaaaaaaaabaabbbbbaaaabbabbbaaaaaabababbaaaabaaaaaaaaabaaaaaaaabaaaaaabbaaaaabaaaaaababaaababaaaabaaaaaabaaaaaaabaaaaabbaaaaabaababaaaabbaaabbaabaabaaaaababbababaaabbbabaabaaabaaabaababbabaababaaaaabaaababaaaaaaaaaabbaaaabaa...

output:

36

result:

ok single line: '36'

Test #9:

score: 30
Accepted
time: 1ms
memory: 6028kb

input:

1000
aaaaaabaabaaaaaaabaaaaaabaabaaaaaaaaabaabaaaaaaababaaaaabaaabaabaaabaaaaaaaaaaaaabbbbbabaaaaaaabaaaaabaaabaaaaabababaaabaaabaabaabaaaabbaabaaaaaaaaaaaaaaabbaaaaabaabbabbbaaabbbabaababbaabaaaabbaaaabaabbbaaaaaaaaaabaabaaaabbaaaabbbbaaabaaaaabaaababaaaaaaaaaabbabbabaaaaaaaaaaaaaaaabaababbaaaababa...

output:

50

result:

ok single line: '50'

Test #10:

score: 30
Accepted
time: 0ms
memory: 5900kb

input:

1000
aaccbdbabdaaddabaabaaaacbbccdbabbaacabcdababdcacadababaadaaaadabacababcdbaabaaaabdbabbdcaacccaaacababaacbcacaaabbabbaaabcbaaabaababbaaacbaacaaacabdccbbbaabaccacadbbcaabacadaababbaaabababbacaabbaaabcdaabaaaaaabaababaabcabacaabacaaaaaacaaabcbcabcbbcbbbaacaadadbadbbadcabababcabbcbbdadbdababaaadcab...

output:

20

result:

ok single line: '20'

Subtask #2:

score: 20
Accepted

Test #11:

score: 20
Accepted
time: 22ms
memory: 7916kb

input:

100000
ibhqhodaqcwqggmckoemulhkgbfidceskhefhsonccepfodalabaqgobpgcnaervbccadkbtsdigsoqochklocgbjjqcdhwrlacamprsoilyhiwkkjalicedhbxajrkhjgivjhnfdibkdwtexnnriegejazmohlfijbeigfmpngncokxhifjfuwuogccdfglfbxobnarmgfhgpnjjewicgfhcmfbbnjbbjjtbprnagpchcihcihfhcikeaecefdgeegtzlfdolhfieahiehdfcaflmndmcojceblf...

output:

9

result:

ok single line: '9'

Test #12:

score: 20
Accepted
time: 18ms
memory: 7840kb

input:

100000
fruiifpdggdnsbgamakpjipicaidfdjpffioqcwioaafbpdagmbbakqpekjabcljockpvcifilcjakhcboolgjbnmmrbeawcjopbccjgncdaucighprheiaqofriccfdbydbhijeelbthsmqbhcddlfemqkvdbflkdrifckarqwlaafifmqibssfukblchalkzdefnccaiabrhcrmisdeiqddccrqhiiwcqqakbfhebkiecahgdlibhgmegkfbuibcarcbajpdeboigeoctdljmqeckdfqahiecla...

output:

9

result:

ok single line: '9'

Test #13:

score: 20
Accepted
time: 21ms
memory: 7844kb

input:

99999
biwnbsgdlxognjnepijlgbfbbahicjfqhdhcielcovdflacbrgcfapifaylqfmvipcccoofthuutfheboncacenchdgfljpidjbasdsikduidkbdqckmlnbfaidlincqkccbbpmnqnpbjoclgeduitraqmdfgdqinhddgberlbnlgggoafgqllbifekoccpgemcgdiiackkcfjgddhieabhzdjfwegcbuncdadebglitgwcbpmclfijmqtbbnbbrcehhanjgbddiaoimmkehtloreemecckjejifck...

output:

11

result:

ok single line: '11'

Test #14:

score: 20
Accepted
time: 23ms
memory: 7840kb

input:

99999
chgjcjipccsmclcpjqmbrcpaqdggbdodxbcejbklpjhkefeidkjojjjbljhtykbcdgnnjeictgjgliegyfilmlkqkgddpefibjusamblbpqfbbvcfkgfagikbujlbjvenjbmcadceadnltdeksatckmkjkscojeqbpaaglggxhideqhkhibchdasadfggcoihhcwlphbeevohhohtthepedqfggbdglidnatocrkhnkijraddqbesaiajimdhdmvbgodlcglqqmkeehcfabeaatjdinzhijewfoxhh...

output:

9

result:

ok single line: '9'

Test #15:

score: 20
Accepted
time: 22ms
memory: 7828kb

input:

99999
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa...

output:

99999

result:

ok single line: '99999'

Subtask #3:

score: 50
Accepted

Dependency #1:

100%
Accepted

Dependency #2:

100%
Accepted

Test #16:

score: 50
Accepted
time: 22ms
memory: 7844kb

input:

100000
vucutyzmjlnyadjbpqkrlqvzuponzxrvqsqqgbemhzjftdkksfgspeuonmjwlbirvszhcafcxpeubixvxetwyyqmftbobhodwaiwrcwdvddohalyqgaatvpflorvjypszbvzpwiaxxgievaozquixcndkxqfxcxaiygyqcgdebogwzquvqfljgjcvvhpirfzqlkwctibngdsffpormliyhrkcbxwxoaoovaawldfenziwnlahllzhjsvdhzekcqekayusmvzrgsdiiymjxfiddhawhgxathvnsedf...

output:

10

result:

ok single line: '10'

Test #17:

score: 50
Accepted
time: 21ms
memory: 7828kb

input:

100000
fotxrzsqxuaaiiqmiymhtfdipylgdmxizgzqrgbrmdemonbisusgbmmsgtyoaqgdmxwoxayxkszpvpypzjoapilopvhyiyhckcccaalqriunudgfifgvdiufjtukpsmdfjjzftszwizrwoxuqsujchtrywpiiineoscbvarbalizfyydbctxpuwndzgshavpygfcmxkorbcppbatauqqkumaqsjcupnihewaukjajqgdvatobxjgdcbevlxpkjdvpofwtctivkexpwnbwvwbhcmlivuvifpptiupy...

output:

9

result:

ok single line: '9'

Test #18:

score: 50
Accepted
time: 34ms
memory: 7664kb

input:

100000
baaabababbbaabbbbaabbabbababbbbbaaaaabaabbbbbbaaabaabaaabababbabbabbaababbaababbbabaaaaabbbabbabaaaabaabbbbababaaaaabbbbbabbbababbbbbaaabbaaabaabaaababbababbabaaaaaaaababaaabaababbbababbbbabbbabaaababbababbbababaabbaabbabaaaabaaabbbabbaabbabbbbbbabbbbaaaaaaaaaaabbbaabaaaabbbabbbaabababbbbaabb...

output:

40

result:

ok single line: '40'

Test #19:

score: 50
Accepted
time: 32ms
memory: 7704kb

input:

100000
babbbbaabaaaaaaaaaabbbbababababababababbabaaabbaaaaabaaaabaaaaababaabaabaabbbbabbbaabababbbaaabaaaaaaababaabababababbaabbbaabaabbbbbbbabaabbaabaaaababbbaabaaabaaaabbabbababbaabbabbbaabbbaababbaabaabaabbabbbabaaaaaaaaaabaabbabaaaaababaabbababbbabababbbbabbbbababababaabbabbababbaababababbbbaaba...

output:

43

result:

ok single line: '43'

Test #20:

score: 50
Accepted
time: 35ms
memory: 7780kb

input:

100000
aabaabbaaaaabbbbbaaaaaaaaaaaaaabbaaaaaaaaabaaaabbaaaaaabaaaaabaabbaaabababaaabbaaaaaaaaaabbabbbaaaaaaabaaabbbaabaaabaaabaaaaaaaaaabaabaaaababaaaaaabbaaaaaaababaabaaaaabababaaaaaaaaaababaaaababbaaabaaaabaaaaabaababbaaaaabbaaabaabaabaaaaababaaaaabbaaaabaaaaaaabaaaaaaaaabaabaaaaaabaababbbabaaaba...

output:

75

result:

ok single line: '75'

Test #21:

score: 50
Accepted
time: 29ms
memory: 7864kb

input:

100000
aaaabaabaaabaabbaaaabbbaaaaaaabaabaabaabaaaababaaaaabaaaaabbabaabbaabaaaaaabaaaaaaaaaaaaabaabbabaaaaaabaaaaaaaaaaaabaaaabbbabaaaaaabaaaababaaaabaaaaaabbaaaaaaaaabababaaaaabaabababaaabbababaaaaababababbaaaaaabaabaaaabbababbbaaabaaaabaabaaaaabaabaaaaaabbbaaaaaaabababababbaaabaaabaaababaaaabaaaa...

output:

58

result:

ok single line: '58'

Test #22:

score: 50
Accepted
time: 35ms
memory: 7788kb

input:

100000
abbaaaaaaabaaaaaaaabaaaaaaaaaaaaaaaaabbabaaabaaaaaaaaaaaaaaabaaabbbaabaaaaabaaaaaaabaaaaabaabaabaaaababaaaaaaaaaaaaaaaaabaaabbabaaaaaaabaaaaaaabaaaaaabaaaaabaaabbaaaabbaabbaaababaababaaaaaabaaaaabaaaaaaaaaaaaababaaaaabaaaaaabbbabaaaaaaaaaaaaabaaaaaaaabbbaabaaabaaabaaabbabaabaaabbabaaaaaaaabba...

output:

67

result:

ok single line: '67'

Test #23:

score: 50
Accepted
time: 31ms
memory: 7772kb

input:

100000
bbaaaaabaaaaaaaaaabbaabaaaaaaabbbaabababaaababbaaaabaaaaaaaaaabaaaabbaaaaabaaaaaabbaabbbbaaabbaaaaaabbabaaabaababbaababaaabaaaaaaaaaabaaaaabbaaaaabbaaaabaaabababbbaabaaaaabaabaaaaaaabaaaaaaabaabababbbaaaaaaaaaaaaaaaaabaaaaaaabaaaaaababbbababaabaaabbbaaaaabaaaaaaabaabababaaaaaabaaaabbaabababaa...

output:

55

result:

ok single line: '55'

Test #24:

score: 50
Accepted
time: 28ms
memory: 7704kb

input:

100000
cabcacbbacbbaacbaabbaabbaabacdcadbbccabbccbbaabacacbabaccbaabbbaaabaddbcaccdcaababaaabbbbbcdacaabababcbbcbcabbbdbbbcadaadabcabbacabbdbbcaaabacaabbabbabacbabbabaadabbabdbabcbdcaacaddbbbabdabaaabcabcababbcbbaaccabbbbacaabbacdaaaabaaaaccaaabaaccbaccbbababdacaacabcaaabbaaacbcbaaabcaaabcaabbabbcad...

output:

25

result:

ok single line: '25'

Test #25:

score: 50
Accepted
time: 25ms
memory: 7848kb

input:

100000
abbabbababbabbababbababbabbababbabbababbababbabbababbababbabbababbabbababbababbabbababbabbababbababbabbababbababbabbababbabbababbababbabbababbababbabbababbabbababbababbabbababbabbababbababbabbababbababbabbababbabbababbababbabbababbabbababbababbabbababbababbabbababbabbababbababbabbababbababbab...

output:

96421

result:

ok single line: '96421'

Test #26:

score: 50
Accepted
time: 1ms
memory: 4408kb

input:

5
pkusc
pkukp

output:

6

result:

ok single line: '6'