#include <bits/stdc++.h>
#define bp __builtin_popcountll
#define pb push_back
#define in(s) freopen(s, "r", stdin);
#define out(s) freopen(s, "w", stdout);
#define inout(s, end1, end2) freopen((string(s) + "." + end1).c_str(), "r", stdin),\
freopen((string(s) + "." + end2).c_str(), "w", stdout);
#define fi first
#define se second
#define bw(i, r, l) for (int i = r - 1; i >= l; i--)
#define fw(i, l, r) for (int i = l; i < r; i++)
#define fa(i, x) for (auto i: x)
using namespace std;
const int mod = 1e9 + 7, inf = 1061109567;
const long long infll = 4557430888798830399;
const int N = 405;
int n, dp[N][405][N][3], cntPrefix[N][3];
string s;
vector<int> reds, greens, yellows;
int getRealPosition(int ogPos, int prvRed, int prvGreen, int prvYellow) {
//prvRed - cntPrefix[ogPos][0] is the number of reds that are moved to before ogPos
int ans = 0;
ans += max(0, prvRed - cntPrefix[ogPos][0]);
ans += max(0, prvGreen - cntPrefix[ogPos][1]);
ans += max(0, prvYellow - cntPrefix[ogPos][2]);
return ogPos + ans + 1; //Difference between array indices and dp indices.
}
signed main() {
#ifdef BLU
in("blu.inp");
#endif
ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
cin >> n >> s;
fw (i, 0, s.length()) {
if (s[i] == 'R') reds.pb(i);
else if (s[i] == 'G') greens.pb(i);
else yellows.pb(i);
}
//0: red, 1: green, 2: yellow
fw (i, 0, s.length()) {
fw (color, 0, 3) cntPrefix[i][color] = (i ? cntPrefix[i - 1][color] : 0);
if (s[i] == 'R') cntPrefix[i][0]++;
else if (s[i] == 'G') cntPrefix[i][1]++;
else cntPrefix[i][2]++;
}
fw (i, 1, n + 1) fw (r, 0, min((i + 1) / 2, (int)reds.size()) + 1) fw (g, 0, min(i - r, (int)greens.size()) + 1)
fw (color, 0, 3) dp[i][r][g][color] = inf;
//dp(i, r, g, color): Minimal cost for the first i items, j reds and k greens, i - j - k yellows. The
//last leave is colored "color".
if (reds.size() > 0) dp[1][1][0][0] = reds[0];
if (greens.size() > 0) dp[1][0][1][1] = greens[0];
if (yellows.size() > 0) dp[1][0][0][2] = yellows[0];
fw (i, 2, n + 1) fw (r, 0, min((i + 1) / 2, (int)reds.size()) + 1) fw (g, 0, min(i - r, (int)greens.size()) + 1)
fw (color, 0, 3) {
// cout << "dp[" << i << "][" << r << "][" << g << "][" << color << "]\n";
if (color == 0 && r == 0) continue;
if (color == 1 && g == 0) continue;
if (color == 2 && i - r - g == 0) continue;
fw (prvColor, 0, 3) if (prvColor != color) {
int newr = r, newg = g;
if (color == 0) newr--;
if (color == 1) newg--;
if (newr < 0 || newg < 0) continue;
dp[i][r][g][color] = min(dp[i][r][g][color], dp[i - 1][newr][newg][prvColor]);
}
if (dp[i][r][g][color] == inf) continue; //Non - valid state
int y = i - r - g;
if (y > yellows.size()) continue;
if (color == 0) {
dp[i][r][g][color] += getRealPosition(reds[r - 1], r - 1, g, y) - i;
} else if (color == 1) {
dp[i][r][g][color] += getRealPosition(greens[g - 1], r, g - 1, y) - i;
} else {
dp[i][r][g][color] += getRealPosition(yellows[y - 1], r, g, y - 1) - i;
}
}
int ans = inf;
fw (color, 0, 3) ans = min(ans, dp[n][reds.size()][greens.size()][color]);
if (ans == inf) cout << "-1";
else cout << ans;
return 0;
}
Compilation message
joi2019_ho_t3.cpp: In function 'int main()':
joi2019_ho_t3.cpp:11:39: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
#define fw(i, l, r) for (int i = l; i < r; i++)
joi2019_ho_t3.cpp:34:6:
fw (i, 0, s.length()) {
~~~~~~~~~~~~~~~~
joi2019_ho_t3.cpp:34:2: note: in expansion of macro 'fw'
fw (i, 0, s.length()) {
^~
joi2019_ho_t3.cpp:11:39: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
#define fw(i, l, r) for (int i = l; i < r; i++)
joi2019_ho_t3.cpp:40:6:
fw (i, 0, s.length()) {
~~~~~~~~~~~~~~~~
joi2019_ho_t3.cpp:40:2: note: in expansion of macro 'fw'
fw (i, 0, s.length()) {
^~
joi2019_ho_t3.cpp:68:9: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
if (y > yellows.size()) continue;
~~^~~~~~~~~~~~~~~~
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
2 ms |
376 KB |
Output is correct |
| 2 |
Correct |
2 ms |
376 KB |
Output is correct |
| 3 |
Correct |
2 ms |
376 KB |
Output is correct |
| 4 |
Incorrect |
2 ms |
504 KB |
Output isn't correct |
| 5 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
2 ms |
376 KB |
Output is correct |
| 2 |
Correct |
2 ms |
376 KB |
Output is correct |
| 3 |
Correct |
2 ms |
376 KB |
Output is correct |
| 4 |
Incorrect |
2 ms |
504 KB |
Output isn't correct |
| 5 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Incorrect |
2 ms |
376 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
2 ms |
376 KB |
Output is correct |
| 2 |
Correct |
2 ms |
376 KB |
Output is correct |
| 3 |
Correct |
2 ms |
376 KB |
Output is correct |
| 4 |
Incorrect |
2 ms |
504 KB |
Output isn't correct |
| 5 |
Halted |
0 ms |
0 KB |
- |
