#include <bits/stdc++.h>
#pragma GCC optimize("Ofast")
#define AquA cin.tie(0);ios_base::sync_with_stdio(0);
#define fs first
#define sc second
#define p_q priority_queue
#define int long long
using namespace std;
signed main(){
AquA;
int n;
cin >> n;
string s;
cin >> s;
int ans=1e14;
vector<int> a,b;
for(int i=0;i<n;i++){
if(s[i]=='B'){
a.push_back(i);
}
if(s[i+n]=='W'){
b.push_back(i);
}
}
int nn=n;
n=a.size();
vector<int> mp(n,-1);
auto f=[&](int i){
if(i>=n || i<0){
return 41232432433;
}
if(mp[i]>=0){
return mp[i];
}
int xx=0;
for(int j=0;j<n;j++){
xx+=min(abs(b[j]-a[(i+j)%n]),nn-abs(b[j]-a[(i+j)%n]));
}
ans=min(ans,xx);
mp[i]=xx;
return xx;
};
if(0 && n<=2000){
if(n==0){
ans=0;
}
for(int i=0;i<n;i++){
f(i);
}
cout << nn*(nn-1)/2-ans << "\n";
return 0;
}
int z;
if(n){
if(f(0)>f(n-1)){
z=n-1;
int l=0,r=n-1;
while(r>l){
int m=(l+r)/2;
if(f(m)<=f(z)){
r=m;
}
else{
l=m+1;
}
}
int bl=l,br=n-1;
while(br>bl+1){
int m=(bl+br)/2;
if(f(m)>f(m+1)){
bl=m;
}
else{
br=m-1;
}
}
f(bl);
f(br);
}
else{
z=0;
int l=0,r=n-1;
while(r>l){
int m=(l+r+1)/2;
if(f(m)<=f(z)){
l=m;
}
else{
r=m-1;
}
}
int bl=0,br=l;
while(br>bl+1){
int m=(bl+br)/2;
if(f(m)>f(m+1)){
bl=m;
}
else{
br=m-1;
}
}
f(bl);
f(br);
}
}
else{
ans=0;
}
cout << nn*(nn-1)/2-ans << "\n";
return 0;
}
Compilation message
monochrome.cpp: In lambda function:
monochrome.cpp:34:24: error: inconsistent types 'long int' and 'long long int' deduced for lambda return type
34 | return mp[i];
| ^
monochrome.cpp:42:16: error: inconsistent types 'long int' and 'long long int' deduced for lambda return type
42 | return xx;
| ^~