QOJ.ac
QOJ
ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
---|---|---|---|---|---|---|---|---|---|
#557239 | #8668. 回文路径 | lichenghan | 100 ✓ | 35ms | 7916kb | C++14 | 1.8kb | 2024-09-11 08:21:17 | 2024-09-11 08:21:18 |
Judging History
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'