제출 #1055847

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1055847		pawned	Catfish Farm (IOI22_fish)	C++17	12 / 100	50 ms	20304 KiB

fish

#pragma GCC optimize("O1,O2,O3,Ofast,unroll-loops")

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

#define fi first
#define se second
#define pb push_back
typedef long long ll;
typedef pair<ll, ll> ii;
typedef vector<ll> vi;

#include "fish.h"

ll max_weights(int N, int M, vector<int> X_g, vector<int> Y_g, vector<int> W_g) {
	vi a(N);
	for (int i = 0; i < M; i++) {
		a[X_g[i]] += W_g[i];
	}
/*	cout<<"a: ";
	for (ll x : a)
		cout<<x<<" ";
	cout<<endl;*/
	vector<vi> dp(N + 1, vi(2, 0));
	// dp[i][j]: max sum till i, exclusive; j = 0 if no pier, j = 1 if has
	dp[0][1] = -1e18;
	for (int i = 1; i <= N; i++) {
		// a[i - 1] is empty
		dp[i][0] = dp[i - 1][0];
		dp[i][0] = max(dp[i][0], dp[i - 1][1] + a[i - 1]);
		// a[i - 1] is filled
		dp[i][1] = dp[i - 1][1];	// left also filled
		if (i >= 2)
			dp[i][1] = max(dp[i][1], max(dp[i - 2][0], dp[i - 2][1]) + a[i - 2]);
	}
/*	cout<<"dp: "<<endl;
	for (vi v : dp) {
		for (ll x : v)
			cout<<x<<" ";
		cout<<endl;
	}*/
	return max(dp[N][0], dp[N][1]);
}

// subtasks 1, 2: greedy
// subtask 3: dp

// code subtask 3 first to verify correct dp

• Subtask 1: 3 / 3
• Subtask 2: 0 / 6
• Subtask 3: 9 / 9
• Subtask 4: 0 / 14
• Subtask 5: 0 / 21
• Subtask 6: 0 / 17
• Subtask 7: 0 / 14
• Subtask 8: 0 / 16