Submission #1082618

#	Time	Username	Problem	Language	Result	Execution time	Memory
1082618		vjudge1	Catfish Farm (IOI22_fish)	C++17	100 / 100	373 ms	123064 KiB

fish

#include "fish.h"
#include <bits/stdc++.h>
#define ent '\n'

using namespace std;
typedef long long ll;
const int maxn = 1e5 + 12;

vector<int> s[maxn];
vector<ll> dp[maxn], dpt[maxn], d[maxn];
vector<ll> pref[maxn], mx[maxn], suff[maxn];
vector<ll> a[maxn], mval[maxn];

long long max_weights(int n, int m, vector<int> x, vector<int> y, vector<int> w) {
    ll ans = 0;
    for(int i=0;i<m;i++){
        x[i]++, y[i]++;
        for(int d=-1;d<=1;d++){
            s[x[i] + d].push_back(y[i]);
        }
    }
    for(int i=0;i<=n;i++){
        s[i].push_back(0);
        sort(s[i].begin(), s[i].end());
        s[i].resize(unique(s[i].begin(), s[i].end()) - s[i].begin());
        dp[i] = d[i] = pref[i] = mx[i] = suff[i] = a[i] = mval[i] = vector<ll> ((int)s[i].size(), 0);
        dpt[i] = {0};
    }

    for(int i=0;i<m;i++){
        int j = lower_bound(s[x[i]].begin(), s[x[i]].end(), y[i]) - s[x[i]].begin();
        a[x[i]][j] += w[i];
    }
    for(int i=1;i<=n;i++){
        ll sum = 0;
        for(int j=0;j<s[i].size();j++){
            sum += a[i][j];
            pref[i][j] = sum;
        }
    }

    for(int i=1;i<=n;i++){
        dpt[i] = vector<ll> (s[i-1].size(), 0);
        ll val = -1e18;

        for(int j=0;j<(int)s[i].size();j++){
            int x = s[i][j];
            int it = upper_bound(s[i-1].begin(), s[i-1].end(), x) - s[i-1].begin();
            it--;

            dp[i][j] = max(mx[i-1][it] + pref[i-1][it], mval[i-1][it]);
            d[i][j] = max(dp[i][j], suff[i-1][it] - pref[i][j]);
            val = max(val, d[i][j]);
            mval[i][j] = val;
            ans = max(ans, d[i][j]);
        }

        for(int j=0;j<(int)s[i-1].size();j++){
            int x = s[i-1][j];
            int it = upper_bound(s[i].begin(), s[i].end(), x) - s[i].begin();
            it--;
            dpt[i][j] = d[i-1][j] + pref[i][it];
        }

        val = -1e18;

        for(int j=0;j<(int)s[i].size();j++){
            int x = s[i][j];
            int it = upper_bound(s[i-1].begin(), s[i-1].end(), x) - s[i-1].begin();
            it--;

            val = max(val, max(dp[i][j], dpt[i][it]) - pref[i][j]);
            mx[i][j] = val;
        }

        val = -1e18;

        if(i < n){
            for(int j=(int)s[i].size() - 1;j>=0;j--){
                int x = s[i][j];
                int it = upper_bound(s[i+1].begin(), s[i+1].end(), x) - s[i+1].begin();
                it--;

                val = max(val, d[i][j] + pref[i+1][it]);
                suff[i][j] = val;
            }
        }
    }
    return ans;
}

Compilation message (stderr)

fish.cpp: In function 'long long int max_weights(int, int, std::vector<int>, std::vector<int>, std::vector<int>)':
fish.cpp:36:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   36 |         for(int j=0;j<s[i].size();j++){
      |                     ~^~~~~~~~~~~~

• 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