Submission #291568

#	Time	Username	Problem	Language	Result	Execution time	Memory
291568		reymontada61	Growing Vegetable is Fun 3 (JOI19_ho_t3)	C++14	100 / 100	151 ms	189944 KiB

joi2019_ho_t3

#include <bits/stdc++.h>
using namespace std;

int n;
string s;
int r, g, b;
const int MXN = 405;
int dp[MXN][MXN][MXN][4];

vector<int> rs, gs, bs;

int pfr[MXN];
int pfg[MXN];
int pfb[MXN];

signed main() {


	cin >> n >> s;
	
	int rc = 0, bc = 0, gc = 0;
	
	for (int i=0; i<n; i++) {
		if (s[i] == 'R') {
			rs.push_back(i+1);
			r++;
			rc++;
		}
		if (s[i] == 'G') {
			gs.push_back(i+1);
			g++;
			gc++;
		}
		if (s[i] == 'Y') {
			bs.push_back(i+1);
			b++;
			bc++;
		}
		pfr[i+1] = r;
		pfg[i+1] = g;
		pfb[i+1] = b;
	}
	
	s = ' ' + s;
	
	for (int ind=1; ind<=n; ind++) {
		for (int r=0; r<=rc; r++) {
			for (int g=0; g<=gc; g++) {
				int b = ind - r - g;
				if (b >= 0 && b <= bc) {
					for (int whi=1; whi<=3; whi++) {
						
						int re = INT_MAX / 2;
						
						if (whi != 1 && r > 0) {
							int h = dp[ind-1][r-1][g][1];
							int l = rs[r-1];
							h += max(l + max(g - pfg[l], 0) + max(b - pfb[l], 0) - ind, 0);
							re = min(re, h);
						}
						
						if (whi != 2 && g > 0) {
							int h = dp[ind-1][r][g-1][2];
							int l = gs[g-1];
							h += max(l + max(b - pfb[l], 0) + max(r - pfr[l], 0) - ind, 0);
							re = min(re, h);
						}
						
						if (whi != 3 && b > 0) {
							int h = dp[ind-1][r][g][3];
							int l = bs[b-1];
							h += max(l + max(g - pfg[l], 0) + max(r - pfr[l], 0) - ind, 0);
							re = min(re, h);
						}
						
						dp[ind][r][g][whi] = re;	
					}
				}
			}
		}
	}

	
	int re = dp[n][r][g][1];
	for (int i=1; i<=3; i++) re = min(re, dp[n][r][g][i]);
	
	if (re > n * n * 2) {
		cout << -1 << endl;
	}
	else {
		cout << re << endl;
	}

}

• Subtask 1: 5 / 5
• Subtask 2: 55 / 55
• Subtask 3: 15 / 15
• Subtask 4: 25 / 25