#include <bits/stdc++.h>
using namespace std;
#define rep(i,a,b) for(int i=(a);i<(b);i++)
#define per(i,a,b) for(int i=(b)-1;i>=(a);i--)
using ll=long long;
using vi=vector<int>;
//pi[i] = longitud del prefijo propio mas grande de s[0..i] que tambien es sufijo
vi prefix_function(string s) {
vi pi(s.size());
for(int i=1,j=0; i<s.size(); i++) {
while(j && s[i]!=s[j]) j=pi[j-1];
if(s[i]==s[j]) j++;
pi[i] = j;
}
return pi;
}
// Busca las coincidencias de p en s, regresa indices de inicio
vi kmp(string s, string p) {
vi pi = prefix_function(p);
vi ans(s.size());
for(int i=0,j=0; i<s.size(); i++) {
while(j && s[i]!=p[j]) j=pi[j-1];
if(s[i]==p[j]) j++;
ans[i]=j;
if(j==p.size()) {
j=pi[j-1];
}
}
return ans;
}
int main(){
ios_base::sync_with_stdio(0);
string s,t;
cin>>s>>t;
int n=s.size(),m=t.size(),ans=0,l=0,r=0;
vector<vi> lps(m),lsp(n);
rep(k,0,m) {
string p=t.substr(k);
lps[k]=kmp(s,p);
}
rep(k,0,n) {
string p=s.substr(k);
lsp[k]=kmp(t,p);
}
rep(i,0,n-1) rep(j,0,m-1) {
int a=lps[j+1][i],b=lsp[i+1][j];
if(ans<a+b) ans=a+b,l=i-a+1,r=j-b+1;
}
reverse(s.begin(),s.end());
rep(k,0,m) {
string p=t.substr(k);
lps[k]=kmp(s,p);
}
rep(k,0,n) {
string p=s.substr(k);
lsp[k]=kmp(t,p);
}
rep(i,0,n-1) rep(j,0,m-1) {
int a=lps[j+1][i],b=lsp[i+1][j];
if(ans<a+b) ans=a+b,l=n-i-a-1,r=j-b+1;
}
cout<<ans<<"\n";
cout<<l<<" "<<r<<"\n";
}
Compilation message
necklace.cpp: In function 'vi prefix_function(std::string)':
necklace.cpp:10:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
10 | for(int i=1,j=0; i<s.size(); i++) {
| ~^~~~~~~~~
necklace.cpp: In function 'vi kmp(std::string, std::string)':
necklace.cpp:21:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
21 | for(int i=0,j=0; i<s.size(); i++) {
| ~^~~~~~~~~
necklace.cpp:25:13: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
25 | if(j==p.size()) {
| ~^~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
156 ms |
65540 KB |
Execution killed with signal 9 |
| 2 |
Halted |
0 ms |
0 KB |
- |
