#include <bits/stdc++.h>
using namespace std;
#define dbgv(v) cout<<#v<<" = "; f(i,0,v.size()) cout<<v[i]<<" "; cout<<endl
#define dbga(a,x,y) cout<<#a<<" = "; f(i,x,y) cout<<a[i]<<" "; cout<<endl
#define erorp(x) cout<<#x<<"={"<<(x.F)<<" , "<<x.S<<"}"<<endl
#define eror(x) cout<<#x<<'='<<(x)<<endl
#define f_(i,a,b) for(int i=a;i>=b;i--)
#define f(i,a,b) for(int i=a;i<b;i++)
#define nb(x) __builtin_popcount(x)
#define all(v) v.begin(),v.end()
#define bit(n,k) (((n)>>(k))&1)
#define Add(x,y) x=(x+y)%mod
#define maxm(a,b) a=max(a,b)
#define minm(a,b) a=min(a,b)
#define lst(x) x[x.size()-1]
#define sz(x) int(x.size())
#define mp make_pair
#define ll long long
#define pb push_back
#define S second
#define F first
const int N=4e5+99;
int n,a[N],L[N],R[N],fenwik[N];
string s;
vector<int> vec0,vec1;
void add(int x, int val){ for (x++;x>0;x-=x&-x) fenwik[x]+=val; }
int get(int x) { int res=0; for(x++;x<N;x+=x&-x) res+=fenwik[x]; return res; }
ll calc(int shift){
f(i,0,N) fenwik[i]=0;
ll res=0;
f(i,0,n){
L[i]=min(vec0[i],vec1[(i+shift)%n]);
R[i]=max(vec0[i],vec1[(i+shift)%n]);
a[L[i]]=i;
a[R[i]]=i;
}
f(i,0,2*n){
if(L[a[i]]==i){
add(i,1);
}
else{
add(L[a[i]],-1);
res+=get(L[a[i]]);
}
}
return res;
}
int32_t main(){
ios:: sync_with_stdio(0), cin.tie(0), cout.tie(0);
cin>>n>>s;
f(i,0,2*n) if(s[i]==s[0]) vec0.pb(i); else vec1.pb(i);
int l=-1,r=n-1;
while(l+1<r){
int mid=(l+r)>>1;
if(calc(mid)<calc(mid+1)){
l=mid;
}
else{
r=mid;
}
}
int x=n/2;
ll ans=0;
f(i,max(0,x-2),min(n,x+2)) maxm(ans,calc(i));
cout<<ans;
//cout<<calc(r);
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
1876 KB |
Output is correct |
2 |
Correct |
1 ms |
1876 KB |
Output is correct |
3 |
Correct |
1 ms |
1876 KB |
Output is correct |
4 |
Correct |
1 ms |
1876 KB |
Output is correct |
5 |
Correct |
1 ms |
1876 KB |
Output is correct |
6 |
Correct |
1 ms |
1876 KB |
Output is correct |
7 |
Correct |
1 ms |
1876 KB |
Output is correct |
8 |
Correct |
1 ms |
1876 KB |
Output is correct |
9 |
Correct |
1 ms |
1876 KB |
Output is correct |
10 |
Correct |
1 ms |
1876 KB |
Output is correct |
11 |
Incorrect |
1 ms |
1876 KB |
Output isn't correct |
12 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
1876 KB |
Output is correct |
2 |
Correct |
1 ms |
1876 KB |
Output is correct |
3 |
Correct |
1 ms |
1876 KB |
Output is correct |
4 |
Correct |
1 ms |
1876 KB |
Output is correct |
5 |
Correct |
1 ms |
1876 KB |
Output is correct |
6 |
Correct |
1 ms |
1876 KB |
Output is correct |
7 |
Correct |
1 ms |
1876 KB |
Output is correct |
8 |
Correct |
1 ms |
1876 KB |
Output is correct |
9 |
Correct |
1 ms |
1876 KB |
Output is correct |
10 |
Correct |
1 ms |
1876 KB |
Output is correct |
11 |
Incorrect |
1 ms |
1876 KB |
Output isn't correct |
12 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
1876 KB |
Output is correct |
2 |
Correct |
1 ms |
1876 KB |
Output is correct |
3 |
Correct |
1 ms |
1876 KB |
Output is correct |
4 |
Correct |
1 ms |
1876 KB |
Output is correct |
5 |
Correct |
1 ms |
1876 KB |
Output is correct |
6 |
Correct |
1 ms |
1876 KB |
Output is correct |
7 |
Correct |
1 ms |
1876 KB |
Output is correct |
8 |
Correct |
1 ms |
1876 KB |
Output is correct |
9 |
Correct |
1 ms |
1876 KB |
Output is correct |
10 |
Correct |
1 ms |
1876 KB |
Output is correct |
11 |
Incorrect |
1 ms |
1876 KB |
Output isn't correct |
12 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
1876 KB |
Output is correct |
2 |
Correct |
1 ms |
1876 KB |
Output is correct |
3 |
Correct |
1 ms |
1876 KB |
Output is correct |
4 |
Correct |
1 ms |
1876 KB |
Output is correct |
5 |
Correct |
1 ms |
1876 KB |
Output is correct |
6 |
Correct |
1 ms |
1876 KB |
Output is correct |
7 |
Correct |
1 ms |
1876 KB |
Output is correct |
8 |
Correct |
1 ms |
1876 KB |
Output is correct |
9 |
Correct |
1 ms |
1876 KB |
Output is correct |
10 |
Correct |
1 ms |
1876 KB |
Output is correct |
11 |
Incorrect |
1 ms |
1876 KB |
Output isn't correct |
12 |
Halted |
0 ms |
0 KB |
- |