#include <iostream>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define INF 100000000
//#define int long long
#define lchild(i) (i*2 + 1)
#define rchild(i) (i*2 + 2)
#define mid(l, u) ((l+u)/2)
#define x(p) p.first
#define y(p) p.second
#define MOD 998244353
#define ordered_set tree<pair<int, int>, null_type,less<pair<int, int>>, rb_tree_tag,tree_order_statistics_node_update>
using namespace std;
int n;
const int N = 401;
int dp[N][N][N][3];
int g[3][N];
int cc[] = {0, 0, 0};
int cmp[N][3];
signed main(){
ios_base::sync_with_stdio(false);
cin.tie(NULL);
cin>>n;
char c;
for(int i = 1;i<=n;i++){
cmp[i][0] = cc[0];
cmp[i][1] = cc[1];
cmp[i][2] = cc[2];
cin>>c;
if(c=='R') g[0][cc[0]++] = i;
else if(c=='G') g[1][cc[1]++] = i;
else g[2][cc[2]++] = i;
}
if(n==1){
cout<<1<<"\n";
}
for(int i = 0;i<=n;i++) for(int j = 0;j<=n;j++) for(int k = 0;k<=n;k++) for(int x = 0;x<3;x++) dp[i][j][k][x] = INF;
for(int i = n-1;i>=1;i--){
for(int aused = n;aused>=0;aused--){
for(int bused = n;bused >= 0 ;bused--){
int cused = i - (aused + bused);
int ause = INF, buse = INF, cuse = INF;
if(aused>cc[0] || bused>cc[1] || cused>cc[2]) continue;
if(cused<0) continue;
int currind;
//calculate use[0]
if(cc[0] > aused) {
currind = g[0][aused] + max((int) 0, bused - cmp[g[0][aused]][1]) +
max((int) 0, cused - cmp[g[0][aused]][2]);
ause = (currind - (i + 1)) + ((i == (n - 1)) ? 0 : dp[i + 1][aused + 1][bused][0]);
}
//calculate buse
if(cc[1] > bused) {
currind = g[1][bused] + max((int) 0, aused - cmp[g[1][bused]][0]) +
max((int) 0, cused - cmp[g[1][bused]][2]);
buse = (currind - (i + 1)) + ((i == (n - 1)) ? 0 : dp[i + 1][aused][bused + 1][1]);
}
//calculate cuse
if(cc[2] > cused) {
currind = g[2][cused] + max((int) 0, aused - cmp[g[2][cused]][0]) +
max((int) 0, bused - cmp[g[2][cused]][1]);
cuse = (currind - (i + 1)) + ((i == (n - 1)) ? 0 : dp[i + 1][aused][bused][2]);
}
dp[i][aused][bused][0] = min(buse, cuse);
dp[i][aused][bused][1] = min(ause, cuse);
dp[i][aused][bused][2] = min(buse, ause);
}
}
}
int ans = INF;
ans = min(ans, (g[0][0] - 1) + dp[1][1][0][0]);
ans = min(ans, (g[1][0] - 1) + dp[1][0][1][1]);
ans = min(ans, (g[2][0] - 1) + dp[1][0][0][2]);
if(ans>=INF) ans = -1;
cout<<ans<<"\n";
}
//2^(2k - 1) - 2^(k-1)
/*
4 4
RGWR
GRRG
WGGW
WWWR
5 5
RGRGW
GRRGW
WGGWR
RWRGW
RGWGW
20
YYGYYYGGGGRGYYGRGRYG
*/
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
5 ms |
384 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
5 ms |
384 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
4 ms |
384 KB |
Output is correct |
| 2 |
Correct |
481 ms |
757496 KB |
Output is correct |
| 3 |
Correct |
466 ms |
755292 KB |
Output is correct |
| 4 |
Correct |
479 ms |
757496 KB |
Output is correct |
| 5 |
Correct |
481 ms |
757428 KB |
Output is correct |
| 6 |
Correct |
470 ms |
757624 KB |
Output is correct |
| 7 |
Correct |
477 ms |
755448 KB |
Output is correct |
| 8 |
Correct |
467 ms |
755320 KB |
Output is correct |
| 9 |
Correct |
470 ms |
751608 KB |
Output is correct |
| 10 |
Correct |
476 ms |
757664 KB |
Output is correct |
| 11 |
Correct |
467 ms |
757556 KB |
Output is correct |
| 12 |
Correct |
116 ms |
202872 KB |
Output is correct |
| 13 |
Correct |
217 ms |
357368 KB |
Output is correct |
| 14 |
Correct |
326 ms |
517496 KB |
Output is correct |
| 15 |
Incorrect |
479 ms |
757600 KB |
Output isn't correct |
| 16 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
5 ms |
384 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
