Submission #47608

#	Time	Username	Problem	Language	Result	Execution time	Memory
47608		RezwanArefin01	Boxes with souvenirs (IOI15_boxes)	C++17	20 / 100	27 ms	16508 KiB

boxes

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

typedef long long ll; 

ll dp[1010][1010][2], dp2[15][15][15][2];
vector<int> a; 
int N, K, L; 

ll solve(int l, int r, int side) {
	if(l == r - 1) {
		if(!side) return min(a[l], L - a[l]);
		else return min(a[r], L - a[r]); 
	}
	ll &ret = dp[l][r][side];
	if(ret != -1) return ret; 
	if(side == 0) {
		ret = solve(l + 1, r, 0) + a[l + 1] - a[l]; 
		ret = min(ret, solve(l, r - 1, 1) + a[l] + L - a[r - 1]); 
	} else {
		ret = solve(l, r - 1, 1) + a[r] - a[r - 1];
		ret = min(ret, solve(l + 1, r, 0) + a[l + 1] + L - a[r]);  
	}
	return ret; 
}
ll solve2(int l, int r, int rem, int side) {
	if(l == r - 1) {
		if(!side) return min(a[l], L - a[l]);
		else return min(a[r], L - a[r]); 
	}
	ll &ret = dp2[l][r][rem][side];
	if(ret != -1) return ret; 
	if(side == 0) {
		if(rem) {
			ret = solve2(l + 1, r, rem - 1, 0) + a[l + 1] - a[l]; 
			ret = min(ret, solve2(l, r - 1, rem - 1, 1) + a[l] + L - a[r - 1]); 
		} else {
			ret = solve2(l + 1, r, K - 1, 0) + a[l + 1]; 
			ret = min(ret, solve2(l, r - 1, K - 1, 1) + L - a[r - 1]); 
			ret += min(a[l], L - a[l]);
		}
	} else {
		if(rem) {
			ret = solve2(l, r - 1, rem - 1, 1) + a[r] - a[r - 1];
			ret = min(ret, solve2(l + 1, r, rem - 1, 0) + a[l + 1] + L - a[r]);  
		} else {
			ret = solve2(l, r - 1, K - 1, 1) + L - a[r - 1]; 
			ret = min(ret, solve2(l + 1, r, K - 1, 0) + a[l + 1]); 
			ret += min(a[r], L - a[r]);  
		}
	}
	return ret; 
}
ll delivery(int n, int k, int l, int p[]) {
	N = n, K = k, L = l;
	if(N <= 15) {
		memset(dp2, -1, sizeof dp2); 
		a.push_back(0); 
		for(int i = 0; i < N; i++) 
			a.push_back(p[i]);
		a.push_back(L);

		return solve2(0, N + 1, K, 0); 
	}
	if(K == 1 || N == 1) {
		ll tot = 0; 
		for(int i = 0; i < N; i++) 
			tot += 2 * min(p[i], L - p[i]); 
		return tot; 
	}
	if(N == K) {
		memset(dp, -1, sizeof dp);
		a.push_back(0); 
		for(int i = 0; i < N; i++) 
			a.push_back(p[i]);
		a.push_back(L);

		return solve(0, N + 1, 0);  
	}
}

Compilation message (stderr)

boxes.cpp: In function 'll delivery(int, int, int, int*)':
boxes.cpp:81:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 0 / 15
• Subtask 4: 0 / 15
• Subtask 5: 0 / 20
• Subtask 6: 0 / 30