Submission #720513

#	Time	Username	Problem	Language	Result	Execution time	Memory
720513		Abrar_Al_Samit	Copy and Paste 3 (JOI22_copypaste3)	C++17	62 / 100	551 ms	49668 KiB

copypaste3

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

const int nax = 2503;
const long long INF = 1e18;
const int P = 31;
const int M = 1e9 + 9;

int n;
string s;
long long A, B, C;
long long dp[nax][nax];
long long hv[nax];
long long pw[nax];
int nxt[nax];

int get(int l, int r) {
	long long ret = hv[r] - hv[l-1];
	if(ret<0) ret += M;
	ret = (ret * pw[n-r]) % M;
	return ret;
}
void PlayGround() {
	cin>>n>>s>>A>>B>>C;

	s = '@' + s;

	pw[0] = 1;
	for(int i=1; i<=n; ++i) {
		pw[i] = (pw[i-1] * P) % M;
		hv[i] = (pw[i] * (s[i]-'a'+1)) + hv[i-1];
		hv[i] %= M;
	}

	for(int i=1; i<=n; ++i) {
		for(int j=1; j<=n; ++j) {
			dp[i][j] = INF;
		}
		dp[i][i] = A;
	}

	for(int un=1; un<=n; ++un) {
		memset(nxt, -1, sizeof nxt);
		unordered_map<int, vector<int>>app;
		for(int i=1; i+un-1<=n; ++i) if(un>1) {
			dp[i][i+un-1] = min(dp[i][i+un-1], min(dp[i+1][i+un-1], dp[i][i+un-2]) + A);
		}
		for(int i=n-un+1; i>0; --i) { // not optimal
			int crval = get(i, i+un-1);
			app[crval].push_back(i);

			if(app[crval][0]<=i+un-1) {
				nxt[i] = -1;
				continue;
			}

			int lo = 0, hi = app[crval].size()-1;
			while(lo<hi) {
				int mid = (lo+hi+1)/2;
				if(app[crval][mid]>i+un-1) lo = mid;
				else hi = mid-1;
			}
			nxt[i] = app[crval][lo];
		}

		for(int i=1; i<=n; ++i) {
			for(int j=nxt[i], cnt=2; j!=-1; j=nxt[j], ++cnt) {
				dp[i][j+un-1] = min(dp[i][j+un-1], 
					dp[i][i+un-1]+B+cnt*C + (j+un-1-i+1 - cnt*un) * A);
			}
		}
	}
	cout<<dp[1][n]<<'\n';
	// cerr << "Time elapsed: " << 1.0 * clock() / CLOCKS_PER_SEC << " s.\n";
}
int main() {
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	PlayGround();
	return 0;
}

• Subtask 1: 1 / 1
• Subtask 2: 5 / 5
• Subtask 3: 14 / 14
• Subtask 4: 10 / 10
• Subtask 5: 32 / 32
• Subtask 6: 0 / 38