Submission #1106882

#	Time	Username	Problem	Language	Result	Execution time	Memory
1106882		pit4h	Catfish Farm (IOI22_fish)	C++17	100 / 100	114 ms	29540 KiB

fish

#include "fish.h"

#include<bits/stdc++.h>
using namespace std;
using ll=long long;
using pi=pair<int,int>;
using vi=vector<int>;
#define mp make_pair
#define eb emplace_back
#define x first
#define y second
#define sz(x)int((x).size())
#define all(x)(x).begin(),(x).end()
#define rep(i,a,b)for(int i=(a);i<(b);i++)
#define per(i,a,b)for(int i=(b)-1;i>=(a);i--)
bool ckmin(auto&a,auto b){return b<a?a=b,1:0;}
bool ckmax(auto&a,auto b){return b>a?a=b,1:0;}
#ifdef LOCAL
auto&operator<<(auto&o,pair<auto,auto>p){return o<<"("<<p.x<<", "<<p.y<<")";}
auto operator<<(auto&o,auto x)->decltype(x.end(),o){o<<"{";int i=0;for(auto&e:x)o<<","+!i++<<e;return o<<"}";}
#define debug(X...)cerr<<"["#X"]: ",[](auto...$){((cerr<<$<<"; "),...)<<endl;}(X);
#else
#define debug(...){}
#endif

struct Container {
	ll shift=0,best=0;
	void add(ll delta) {
		shift += delta;
		best += delta;
	}
	void ins(ll v) {
		ckmax(best, v);
	}
	ll get() {
		return best;
	}
};

long long max_weights(int N, int M, vector<int> X, vector<int> Y,
                      vector<int> W) {

	vector<vector<pi>> sweep(N + 2);

	rep(i,0,M) {
		sweep[X[i]+1].eb(Y[i],W[i]);
	}

	rep(i,0,N+2) { 
		sweep[i].eb(N,0);
		sort(all(sweep[i]));	
	}

	vector<vector<ll>> dp(N+2);
	vector<ll> best_dp(N+2);

	rep(i,0,N+2) {
		dp[i].resize(sz(sweep[i]));
	}

	ll ans = 0;

	rep(i,1,N+1) {
		debug(i);
		int ptr_l=0,ptr_r=0;
		ll sum_l=0,sum_cur=0,sum_r=0;

		Container best_l;

		rep(j,0,sz(sweep[i])) {
			auto [y,w] = sweep[i][j];

			while (ptr_l < sz(sweep[i-1]) && sweep[i-1][ptr_l].x < y) {
				sum_l+=sweep[i-1][ptr_l].y;
				best_l.ins(dp[i-1][ptr_l]);
				best_l.add(sweep[i-1][ptr_l].y);
				ptr_l++;	
			}

			while (ptr_r < sz(sweep[i+1]) && sweep[i+1][ptr_r].x < y) {
				sum_r+=sweep[i+1][ptr_r].y;
				ptr_r++;
			}

			ckmax(dp[i][j], best_l.get());	

			ckmax(dp[i+1][ptr_r], best_l.get() + sum_r);         // cur takes from left and right
			ckmax(dp[i+1][ptr_r], best_dp[i-1] + sum_r);         // prev does not take any from column i
			ckmax(dp[i+1][ptr_r], best_dp[i] + sum_r - sum_cur); // prev takes unlimited amount from column i 

			sum_cur+=w;
		}
		
		rep(s,0,2) {
			rep(j,0,sz(sweep[i+s])) {
				ckmax(best_dp[i+s], dp[i+s][j]);
			}
		}
		debug(dp);
	}

	rep(i,0,N+2) {
		rep(j,0,sz(dp[i])) {
			ckmax(ans, dp[i][j]);
		}
	}

	return ans;
}

Compilation message (stderr)

fish.cpp:16:12: warning: use of 'auto' in parameter declaration only available with '-fconcepts-ts'
   16 | bool ckmin(auto&a,auto b){return b<a?a=b,1:0;}
      |            ^~~~
fish.cpp:16:19: warning: use of 'auto' in parameter declaration only available with '-fconcepts-ts'
   16 | bool ckmin(auto&a,auto b){return b<a?a=b,1:0;}
      |                   ^~~~
fish.cpp:17:12: warning: use of 'auto' in parameter declaration only available with '-fconcepts-ts'
   17 | bool ckmax(auto&a,auto b){return b>a?a=b,1:0;}
      |            ^~~~
fish.cpp:17:19: warning: use of 'auto' in parameter declaration only available with '-fconcepts-ts'
   17 | bool ckmax(auto&a,auto b){return b>a?a=b,1:0;}
      |                   ^~~~

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