#include <bits/stdc++.h>
using namespace std;
// macros
typedef long long ll;
typedef long double ld;
typedef pair<int, int> ii;
typedef pair<ll, ll> lll;
typedef tuple<int, int, int> iii;
typedef vector<int> vi;
typedef vector<ii> vii;
typedef vector<iii> viii;
typedef vector<ll> vll;
typedef vector<lll> vlll;
#define REP(a,b,c) for(int a=int(b); a<int(c); a++)
#define RE(a,c) REP(a,0,c)
#define RE1(a,c) REP(a,1,c+1)
#define REI(a,b,c) REP(a,b,c+1)
#define REV(a,b,c) for(int a=int(c-1); a>=int(b); a--)
#define FOR(a,b) for(auto& a : b)
#define all(a) a.begin(), a.end()
#define INF 1e9
#define EPS 1e-9
#define pb push_back
#define popb pop_back
#define fi first
#define se second
#define sz size()
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
// input
template<class T> void IN(T& x) {cin >> x;}
template<class H, class... T> void IN(H& h, T&... t) {IN(h); IN(t...); }
// output
template<class T1, class T2> void OUT(const pair<T1,T2>& x);
template<class T> void OUT(const T& x) {cout << x;}
template<class H, class... T> void OUT(const H& h, const T&... t) {OUT(h); OUT(t...); }
template<class T1, class T2> void OUT(const pair<T1,T2>& x) {OUT(x.fi,' ',x.se);}
template<class... T> void OUTL(const T&... t) {OUT(t..., "\n"); }
template<class H> void OUTLS(const H& h) {OUTL(h); }
template<class H, class... T> void OUTLS(const H& h, const T&... t) {OUT(h,' '); OUTLS(t...); }
//===================//
// Added libraries //
//===================//
//===================//
//end added libraries//
//===================//
void program();
int main() {
ios_base::sync_with_stdio(false);
cin.tie(NULL);
cout.tie(NULL);
program();
}
//===================//
// begin program //
//===================//
const int MX = 1e6;
int n;
string s;
int a[MX][2], N[2];
int cnt[MX][2];
ll getAns(int x) {
ll ans = 0;
RE(i,n) {
int bp = a[i][0];
int wp = a[(x+i)%n][1];
if(wp < bp) wp += 2*n;
int cntB = cnt[wp][0]-cnt[bp+1][0];
int cntW = cnt[wp][1]-cnt[bp+1][1];
ans += min(cntB, n-1-cntW);
ans += min(cntW, n-1-cntB);
}
ans /= 2;
return ans;
}
void program() {
IN(n, s);
s += s;
RE(i,n*4) s[i] = (s[i] == 'B' ? 0 : 1);
RE(i,2) N[i] = 0;
RE(i,n*2) a[N[s[i]]++][s[i]] = i;
cnt[0][0] = 0;
cnt[0][1] = 0;
RE(i,n*4) {
RE(j,2) cnt[i+1][j] = cnt[i][j];
cnt[i+1][s[i]]++;
}
if(n > 2000) {
int lb=-1, ub=-1;
while(lb == -1) {
int i = rng()%n;
if(getAns(i) < getAns((i+1)%n)) lb = i;
}
while(ub == -1) {
int i = rng()%n;
if(getAns(i) > getAns((i+1)%n)) ub = i;
}
if(ub < lb) ub += n;
while(lb != ub) {
int mid=(lb+ub)/2;
if(getAns(mid%n)<getAns(mid+1)) lb=mid+1;
else ub=mid;
}
OUTL(getAns(lb%n));
} else {
ll ans = 0;
RE(i,n) ans = max(ans, getAns(i));
OUTL(ans);
}
}
Compilation message
monochrome.cpp: In function 'void program()':
monochrome.cpp:93:23: warning: array subscript has type 'char' [-Wchar-subscripts]
93 | RE(i,n*2) a[N[s[i]]++][s[i]] = i;
| ^
monochrome.cpp:93:32: warning: array subscript has type 'char' [-Wchar-subscripts]
93 | RE(i,n*2) a[N[s[i]]++][s[i]] = i;
| ^
monochrome.cpp:98:22: warning: array subscript has type 'char' [-Wchar-subscripts]
98 | cnt[i+1][s[i]]++;
| ^
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
384 KB |
Output is correct |
2 |
Correct |
1 ms |
384 KB |
Output is correct |
3 |
Correct |
0 ms |
384 KB |
Output is correct |
4 |
Correct |
1 ms |
384 KB |
Output is correct |
5 |
Correct |
1 ms |
384 KB |
Output is correct |
6 |
Correct |
1 ms |
384 KB |
Output is correct |
7 |
Correct |
0 ms |
384 KB |
Output is correct |
8 |
Correct |
1 ms |
384 KB |
Output is correct |
9 |
Correct |
1 ms |
384 KB |
Output is correct |
10 |
Correct |
0 ms |
384 KB |
Output is correct |
11 |
Correct |
1 ms |
384 KB |
Output is correct |
12 |
Correct |
0 ms |
384 KB |
Output is correct |
13 |
Correct |
1 ms |
384 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
384 KB |
Output is correct |
2 |
Correct |
1 ms |
384 KB |
Output is correct |
3 |
Correct |
0 ms |
384 KB |
Output is correct |
4 |
Correct |
1 ms |
384 KB |
Output is correct |
5 |
Correct |
1 ms |
384 KB |
Output is correct |
6 |
Correct |
1 ms |
384 KB |
Output is correct |
7 |
Correct |
0 ms |
384 KB |
Output is correct |
8 |
Correct |
1 ms |
384 KB |
Output is correct |
9 |
Correct |
1 ms |
384 KB |
Output is correct |
10 |
Correct |
0 ms |
384 KB |
Output is correct |
11 |
Correct |
1 ms |
384 KB |
Output is correct |
12 |
Correct |
0 ms |
384 KB |
Output is correct |
13 |
Correct |
1 ms |
384 KB |
Output is correct |
14 |
Correct |
1 ms |
384 KB |
Output is correct |
15 |
Correct |
1 ms |
384 KB |
Output is correct |
16 |
Correct |
1 ms |
384 KB |
Output is correct |
17 |
Correct |
1 ms |
384 KB |
Output is correct |
18 |
Correct |
1 ms |
384 KB |
Output is correct |
19 |
Correct |
1 ms |
384 KB |
Output is correct |
20 |
Correct |
1 ms |
384 KB |
Output is correct |
21 |
Correct |
1 ms |
384 KB |
Output is correct |
22 |
Correct |
1 ms |
384 KB |
Output is correct |
23 |
Correct |
1 ms |
384 KB |
Output is correct |
24 |
Correct |
1 ms |
384 KB |
Output is correct |
25 |
Correct |
1 ms |
384 KB |
Output is correct |
26 |
Correct |
1 ms |
384 KB |
Output is correct |
27 |
Correct |
1 ms |
384 KB |
Output is correct |
28 |
Correct |
1 ms |
384 KB |
Output is correct |
29 |
Correct |
1 ms |
512 KB |
Output is correct |
30 |
Correct |
1 ms |
384 KB |
Output is correct |
31 |
Correct |
1 ms |
384 KB |
Output is correct |
32 |
Correct |
1 ms |
384 KB |
Output is correct |
33 |
Correct |
1 ms |
384 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
384 KB |
Output is correct |
2 |
Correct |
1 ms |
384 KB |
Output is correct |
3 |
Correct |
0 ms |
384 KB |
Output is correct |
4 |
Correct |
1 ms |
384 KB |
Output is correct |
5 |
Correct |
1 ms |
384 KB |
Output is correct |
6 |
Correct |
1 ms |
384 KB |
Output is correct |
7 |
Correct |
0 ms |
384 KB |
Output is correct |
8 |
Correct |
1 ms |
384 KB |
Output is correct |
9 |
Correct |
1 ms |
384 KB |
Output is correct |
10 |
Correct |
0 ms |
384 KB |
Output is correct |
11 |
Correct |
1 ms |
384 KB |
Output is correct |
12 |
Correct |
0 ms |
384 KB |
Output is correct |
13 |
Correct |
1 ms |
384 KB |
Output is correct |
14 |
Correct |
1 ms |
384 KB |
Output is correct |
15 |
Correct |
1 ms |
384 KB |
Output is correct |
16 |
Correct |
1 ms |
384 KB |
Output is correct |
17 |
Correct |
1 ms |
384 KB |
Output is correct |
18 |
Correct |
1 ms |
384 KB |
Output is correct |
19 |
Correct |
1 ms |
384 KB |
Output is correct |
20 |
Correct |
1 ms |
384 KB |
Output is correct |
21 |
Correct |
1 ms |
384 KB |
Output is correct |
22 |
Correct |
1 ms |
384 KB |
Output is correct |
23 |
Correct |
1 ms |
384 KB |
Output is correct |
24 |
Correct |
1 ms |
384 KB |
Output is correct |
25 |
Correct |
1 ms |
384 KB |
Output is correct |
26 |
Correct |
1 ms |
384 KB |
Output is correct |
27 |
Correct |
1 ms |
384 KB |
Output is correct |
28 |
Correct |
1 ms |
384 KB |
Output is correct |
29 |
Correct |
1 ms |
512 KB |
Output is correct |
30 |
Correct |
1 ms |
384 KB |
Output is correct |
31 |
Correct |
1 ms |
384 KB |
Output is correct |
32 |
Correct |
1 ms |
384 KB |
Output is correct |
33 |
Correct |
1 ms |
384 KB |
Output is correct |
34 |
Correct |
23 ms |
384 KB |
Output is correct |
35 |
Correct |
23 ms |
384 KB |
Output is correct |
36 |
Correct |
22 ms |
384 KB |
Output is correct |
37 |
Correct |
21 ms |
492 KB |
Output is correct |
38 |
Correct |
20 ms |
384 KB |
Output is correct |
39 |
Correct |
22 ms |
384 KB |
Output is correct |
40 |
Correct |
19 ms |
384 KB |
Output is correct |
41 |
Correct |
18 ms |
512 KB |
Output is correct |
42 |
Correct |
23 ms |
384 KB |
Output is correct |
43 |
Correct |
23 ms |
384 KB |
Output is correct |
44 |
Correct |
20 ms |
384 KB |
Output is correct |
45 |
Correct |
23 ms |
384 KB |
Output is correct |
46 |
Correct |
23 ms |
384 KB |
Output is correct |
47 |
Correct |
23 ms |
384 KB |
Output is correct |
48 |
Correct |
25 ms |
384 KB |
Output is correct |
49 |
Correct |
19 ms |
384 KB |
Output is correct |
50 |
Correct |
23 ms |
384 KB |
Output is correct |
51 |
Correct |
23 ms |
384 KB |
Output is correct |
52 |
Correct |
23 ms |
384 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
384 KB |
Output is correct |
2 |
Correct |
1 ms |
384 KB |
Output is correct |
3 |
Correct |
0 ms |
384 KB |
Output is correct |
4 |
Correct |
1 ms |
384 KB |
Output is correct |
5 |
Correct |
1 ms |
384 KB |
Output is correct |
6 |
Correct |
1 ms |
384 KB |
Output is correct |
7 |
Correct |
0 ms |
384 KB |
Output is correct |
8 |
Correct |
1 ms |
384 KB |
Output is correct |
9 |
Correct |
1 ms |
384 KB |
Output is correct |
10 |
Correct |
0 ms |
384 KB |
Output is correct |
11 |
Correct |
1 ms |
384 KB |
Output is correct |
12 |
Correct |
0 ms |
384 KB |
Output is correct |
13 |
Correct |
1 ms |
384 KB |
Output is correct |
14 |
Correct |
1 ms |
384 KB |
Output is correct |
15 |
Correct |
1 ms |
384 KB |
Output is correct |
16 |
Correct |
1 ms |
384 KB |
Output is correct |
17 |
Correct |
1 ms |
384 KB |
Output is correct |
18 |
Correct |
1 ms |
384 KB |
Output is correct |
19 |
Correct |
1 ms |
384 KB |
Output is correct |
20 |
Correct |
1 ms |
384 KB |
Output is correct |
21 |
Correct |
1 ms |
384 KB |
Output is correct |
22 |
Correct |
1 ms |
384 KB |
Output is correct |
23 |
Correct |
1 ms |
384 KB |
Output is correct |
24 |
Correct |
1 ms |
384 KB |
Output is correct |
25 |
Correct |
1 ms |
384 KB |
Output is correct |
26 |
Correct |
1 ms |
384 KB |
Output is correct |
27 |
Correct |
1 ms |
384 KB |
Output is correct |
28 |
Correct |
1 ms |
384 KB |
Output is correct |
29 |
Correct |
1 ms |
512 KB |
Output is correct |
30 |
Correct |
1 ms |
384 KB |
Output is correct |
31 |
Correct |
1 ms |
384 KB |
Output is correct |
32 |
Correct |
1 ms |
384 KB |
Output is correct |
33 |
Correct |
1 ms |
384 KB |
Output is correct |
34 |
Correct |
23 ms |
384 KB |
Output is correct |
35 |
Correct |
23 ms |
384 KB |
Output is correct |
36 |
Correct |
22 ms |
384 KB |
Output is correct |
37 |
Correct |
21 ms |
492 KB |
Output is correct |
38 |
Correct |
20 ms |
384 KB |
Output is correct |
39 |
Correct |
22 ms |
384 KB |
Output is correct |
40 |
Correct |
19 ms |
384 KB |
Output is correct |
41 |
Correct |
18 ms |
512 KB |
Output is correct |
42 |
Correct |
23 ms |
384 KB |
Output is correct |
43 |
Correct |
23 ms |
384 KB |
Output is correct |
44 |
Correct |
20 ms |
384 KB |
Output is correct |
45 |
Correct |
23 ms |
384 KB |
Output is correct |
46 |
Correct |
23 ms |
384 KB |
Output is correct |
47 |
Correct |
23 ms |
384 KB |
Output is correct |
48 |
Correct |
25 ms |
384 KB |
Output is correct |
49 |
Correct |
19 ms |
384 KB |
Output is correct |
50 |
Correct |
23 ms |
384 KB |
Output is correct |
51 |
Correct |
23 ms |
384 KB |
Output is correct |
52 |
Correct |
23 ms |
384 KB |
Output is correct |
53 |
Correct |
62 ms |
9484 KB |
Output is correct |
54 |
Correct |
72 ms |
9484 KB |
Output is correct |
55 |
Correct |
54 ms |
8992 KB |
Output is correct |
56 |
Correct |
62 ms |
9116 KB |
Output is correct |
57 |
Correct |
59 ms |
9240 KB |
Output is correct |
58 |
Correct |
60 ms |
9612 KB |
Output is correct |
59 |
Correct |
60 ms |
9116 KB |
Output is correct |
60 |
Correct |
59 ms |
9116 KB |
Output is correct |
61 |
Correct |
70 ms |
9236 KB |
Output is correct |
62 |
Correct |
59 ms |
9236 KB |
Output is correct |
63 |
Correct |
62 ms |
9112 KB |
Output is correct |
64 |
Correct |
60 ms |
9116 KB |
Output is correct |
65 |
Correct |
57 ms |
8748 KB |
Output is correct |
66 |
Correct |
77 ms |
8992 KB |
Output is correct |
67 |
Correct |
58 ms |
8992 KB |
Output is correct |
68 |
Correct |
65 ms |
8752 KB |
Output is correct |
69 |
Correct |
69 ms |
9360 KB |
Output is correct |
70 |
Correct |
65 ms |
8624 KB |
Output is correct |
71 |
Correct |
62 ms |
9612 KB |
Output is correct |
72 |
Correct |
69 ms |
9484 KB |
Output is correct |
73 |
Correct |
62 ms |
9484 KB |
Output is correct |