#include <bits/stdc++.h>
//#pragma comment(linker, "/stack:200000000")
//#pragma GCC optimize("Ofast")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#define fast ios_base::sync_with_stdio(false);cin.tie(nullptr);cout.tie(nullptr);
#define all(v) v.begin(),v.end()
#define pb push_back
#define sz size()
#define ft first
#define sd second
using namespace std;
typedef long long ll;
typedef pair<ll, ll> pll;
typedef unsigned long long ull;
const int N = 1e6 + 5;
const ll M = 1e8;
const ll inf = 1e18;
const ll mod = 1e9;
const double Pi = acos(-1);
ll binpow(ll x, ll ti) { ll res = 1;while (ti){if(ti & 1)res *= x;x *= x;ti >>= 1; x %= mod; res %= mod;} return res;}
ll binmul(ll x, ll ti) { ll res = 0;while (ti){if(ti & 1)res += x;x += x;ti >>= 1; x %= mod; res %= mod;} return res;}
ll nok(ll a, ll b) { return (a*b)/__gcd(abs(a),abs(b)) * (a*b > 0 ? 1 : -1); }
bool odd(ll n) { return (n % 2 == 1); }
bool even(ll n) { return (n % 2 == 0); }
ll n, ans = inf;
string s;
set <ll> a, b, c;
set <ll>::iterator it1, it2, it3;
vector <ll> pos;
void rec(string res) {
if (res.sz == n) {
for (int i = 1; i < res.sz; ++ i) {
if (res[i] == res[i - 1]) return;
}
ll cnt = 0;
for (int i = 0; i < pos.sz; ++ i) {
for (int j = i + 1; j < pos.sz; ++ j) {
if (pos[i] > pos[j]) ++ cnt;
}
}
ans = min(ans, cnt);
return;
}
if (res.empty()) {
if (it1 != a.end()) {
pos.pb(*it1);
++ it1;
rec(res + "R");
pos.pop_back();
-- it1;
}
if (it2 != b.end()) {
pos.pb(*it2);
++ it2;
rec(res + "G");
pos.pop_back();
-- it2;
}
if (it3 != c.end()) {
pos.pb(*it3);
++ it3;
rec(res + "Y");
pos.pop_back();
-- it3;
}
} else {
if (res.back() == 'R') {
if (it2 != b.end()) {
pos.pb(*it2);
++ it2;
rec(res + "G");
pos.pop_back();
-- it2;
}
if (it3 != c.end()) {
pos.pb(*it3);
++ it3;
rec(res + "Y");
pos.pop_back();
-- it3;
}
} else if (res.back() == 'Y') {
if (it1 != a.end()) {
pos.pb(*it1);
++ it1;
rec(res + "R");
pos.pop_back();
-- it1;
}
if (it2 != b.end()) {
pos.pb(*it2);
++ it2;
rec(res + "G");
pos.pop_back();
-- it2;
}
} else {
if (it1 != a.end()) {
pos.pb(*it1);
++ it1;
rec(res + "R");
pos.pop_back();
-- it1;
}
if (it3 != c.end()) {
pos.pb(*it3);
++ it3;
rec(res + "Y");
pos.pop_back();
-- it3;
}
}
}
}
const void solve(/*Armashka*/) {
cin >> n >> s;
s = " " + s;
for (int i = 1; i <= n; ++ i) {
if (s[i] == 'R') a.insert(i);
else if (s[i] == 'G') b.insert(i);
else c.insert(i);
}
if (a.sz) it1 = a.begin();
else it1 = a.end();
if (b.sz) it2 = b.begin();
else it2 = b.end();
if (c.sz) it3 = c.begin();
else it3 = c.end();
rec("");
if (ans == inf) ans = -1;
cout << ans << "\n";
}
signed main() {
fast;
//freopen("divide.in", "r", stdin);
//freopen("divide.out", "w", stdout);
int tt = 1;
//cin >> tt;
while (tt --) {
solve();
}
}
/*
5 4 4
1 2
3 1
3 4
5 3
4 5 2 3
2 1 3 1
1 3 5
2 3 4 5
2 1 3 1
*/
Compilation message
joi2019_ho_t3.cpp: In function 'void rec(std::string)':
joi2019_ho_t3.cpp:38:13: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'll' {aka 'long long int'} [-Wsign-compare]
38 | if (res.sz == n) {
| ~~~~~~~^~~~
joi2019_ho_t3.cpp:40:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
40 | for (int i = 1; i < res.sz; ++ i) {
| ^
joi2019_ho_t3.cpp:45:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
45 | for (int i = 0; i < pos.sz; ++ i) {
| ^
joi2019_ho_t3.cpp:46:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
46 | for (int j = i + 1; j < pos.sz; ++ j) {
| ^
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
204 KB |
Output is correct |
2 |
Correct |
0 ms |
204 KB |
Output is correct |
3 |
Correct |
0 ms |
204 KB |
Output is correct |
4 |
Correct |
1 ms |
204 KB |
Output is correct |
5 |
Correct |
1 ms |
204 KB |
Output is correct |
6 |
Correct |
2 ms |
204 KB |
Output is correct |
7 |
Correct |
1 ms |
312 KB |
Output is correct |
8 |
Correct |
1 ms |
204 KB |
Output is correct |
9 |
Correct |
1 ms |
204 KB |
Output is correct |
10 |
Correct |
0 ms |
204 KB |
Output is correct |
11 |
Correct |
1 ms |
312 KB |
Output is correct |
12 |
Correct |
2 ms |
204 KB |
Output is correct |
13 |
Correct |
1 ms |
308 KB |
Output is correct |
14 |
Correct |
1 ms |
308 KB |
Output is correct |
15 |
Correct |
1 ms |
316 KB |
Output is correct |
16 |
Correct |
0 ms |
308 KB |
Output is correct |
17 |
Correct |
0 ms |
312 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
204 KB |
Output is correct |
2 |
Correct |
0 ms |
204 KB |
Output is correct |
3 |
Correct |
0 ms |
204 KB |
Output is correct |
4 |
Correct |
1 ms |
204 KB |
Output is correct |
5 |
Correct |
1 ms |
204 KB |
Output is correct |
6 |
Correct |
2 ms |
204 KB |
Output is correct |
7 |
Correct |
1 ms |
312 KB |
Output is correct |
8 |
Correct |
1 ms |
204 KB |
Output is correct |
9 |
Correct |
1 ms |
204 KB |
Output is correct |
10 |
Correct |
0 ms |
204 KB |
Output is correct |
11 |
Correct |
1 ms |
312 KB |
Output is correct |
12 |
Correct |
2 ms |
204 KB |
Output is correct |
13 |
Correct |
1 ms |
308 KB |
Output is correct |
14 |
Correct |
1 ms |
308 KB |
Output is correct |
15 |
Correct |
1 ms |
316 KB |
Output is correct |
16 |
Correct |
0 ms |
308 KB |
Output is correct |
17 |
Correct |
0 ms |
312 KB |
Output is correct |
18 |
Execution timed out |
1085 ms |
204 KB |
Time limit exceeded |
19 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
204 KB |
Output is correct |
2 |
Correct |
1 ms |
588 KB |
Output is correct |
3 |
Correct |
1 ms |
588 KB |
Output is correct |
4 |
Correct |
1 ms |
588 KB |
Output is correct |
5 |
Correct |
1 ms |
588 KB |
Output is correct |
6 |
Correct |
1 ms |
588 KB |
Output is correct |
7 |
Correct |
1 ms |
588 KB |
Output is correct |
8 |
Correct |
1 ms |
572 KB |
Output is correct |
9 |
Correct |
1 ms |
572 KB |
Output is correct |
10 |
Correct |
1 ms |
568 KB |
Output is correct |
11 |
Correct |
1 ms |
588 KB |
Output is correct |
12 |
Correct |
0 ms |
332 KB |
Output is correct |
13 |
Correct |
1 ms |
460 KB |
Output is correct |
14 |
Correct |
1 ms |
460 KB |
Output is correct |
15 |
Correct |
1 ms |
588 KB |
Output is correct |
16 |
Correct |
1 ms |
588 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
204 KB |
Output is correct |
2 |
Correct |
0 ms |
204 KB |
Output is correct |
3 |
Correct |
0 ms |
204 KB |
Output is correct |
4 |
Correct |
1 ms |
204 KB |
Output is correct |
5 |
Correct |
1 ms |
204 KB |
Output is correct |
6 |
Correct |
2 ms |
204 KB |
Output is correct |
7 |
Correct |
1 ms |
312 KB |
Output is correct |
8 |
Correct |
1 ms |
204 KB |
Output is correct |
9 |
Correct |
1 ms |
204 KB |
Output is correct |
10 |
Correct |
0 ms |
204 KB |
Output is correct |
11 |
Correct |
1 ms |
312 KB |
Output is correct |
12 |
Correct |
2 ms |
204 KB |
Output is correct |
13 |
Correct |
1 ms |
308 KB |
Output is correct |
14 |
Correct |
1 ms |
308 KB |
Output is correct |
15 |
Correct |
1 ms |
316 KB |
Output is correct |
16 |
Correct |
0 ms |
308 KB |
Output is correct |
17 |
Correct |
0 ms |
312 KB |
Output is correct |
18 |
Execution timed out |
1085 ms |
204 KB |
Time limit exceeded |
19 |
Halted |
0 ms |
0 KB |
- |