Submission #1218139

#	Time	Username	Problem	Language	Result	Execution time	Memory
1218139		orlando	Catfish Farm (IOI22_fish)	C++20	18 / 100	48 ms	7268 KiB

fish

#include <bits/stdc++.h>
#include "fish.h"
using namespace std;
using ll = long long;

int n, m;

ll max_weights(int N, int M, vector<int> X, vector<int> Y, vector<int> W) {
    n = N; m = M;
    bool f = true, s = true, t = true;
    for(int i = 0; i < m; i++) {
        if(X[i] & 1) f = false;
        if(X[i] > 1) s = false;
        if(Y[i] != 0) t = false;
    }
    if(f) {
        ll ans = 0;
        for(int i = 0; i < m; i++) ans += W[i];
        return ans;
    }
    if(s) {
        ll f1 = 0, s1 = 0;
        vector<ll> pref(n+1);
        for(int i = 0; i < m; i++) {
            if(X[i] == 0) f1 += W[i];
            else s1 += W[i];
        }
        if(n <= 2) return max(f1, s1);
        vector<ll> pref1(n+1), pref2(n+1);
        for(int i = 0; i < m; i++) {
            if(X[i] == 0) pref1[Y[i]] += W[i];
            else pref2[Y[i]] += W[i];
        }
        ll ans = max(f1, s1);
        for(int i = 1; i <= n; i++) {
            pref1[i] += pref1[i-1];
            pref2[i] += pref2[i-1];
        }
        for(int i = 0; i < n; i++) {
            ans = max(ans, s1-pref2[i]+pref1[i]);
        }
        return ans;
    }
    if(t) {
        vector<array<array<ll, 2>, 2>> dp(n+1);
        vector<ll> elem(n+1);
        for(int i = 0; i < m; i++) elem[X[i]] = W[i];
        dp[1][1][0] = elem[1]; dp[1][0][1] = elem[0];
        for(int i = 2; i < n; i++) {
            dp[i][0][0] = max(dp[i-1][0][0], dp[i-1][1][0]);
            dp[i][0][1] = max(dp[i-1][1][0], dp[i-1][0][0] + elem[i-1]);
            dp[i][1][0] = max(dp[i-1][0][1] + elem[i], dp[i-1][1][1] + elem[i]);
            dp[i][1][1] = max(dp[i-1][1][1], dp[i-1][0][1]);
        }
        return max({dp[n-1][0][0], dp[n-1][0][1], dp[n-1][1][1], dp[n-1][1][0]});
    }

}

/*int main()
{
    cout << max_weights(5, 4, {0, 1, 0, 1}, {2, 1, 4, 3}, {5, 2, 1, 3});
}*/

Compilation message (stderr)

fish.cpp: In function 'll max_weights(int, int, std::vector<int>, std::vector<int>, std::vector<int>)':
fish.cpp:58:1: warning: control reaches end of non-void function [-Wreturn-type]
   58 | }
      | ^

• Subtask 1: 3 / 3
• Subtask 2: 6 / 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