Submission #678151

#	Time	Username	Problem	Language	Result	Execution time	Memory
678151		Tien_Noob	Knapsack (NOI18_knapsack)	C++17	100 / 100	72 ms	4136 KiB

knapsack

//Make CSP great again
//Vengeance
#include <bits/stdc++.h>
#define TASK "TESTCODE"
#define Log2(x) 31 - __builtin_clz(x)
using namespace std;
const int N = 1e5, M = 2e3;
vector<int> keep[M + 1];
int v[N + 1], w[N + 1], k[N + 1], id[N + 1], s, n;
long long dp[N + 1];
void read()
{
    cin >> s >> n;
    for (int i = 1; i <= n; ++ i)
    {
        cin >> v[i] >> w[i] >> k[i];
        id[i] = i;
    }
    sort(id + 1, id + n + 1, [&](const int &x, const int &y)
         {
             return v[x] > v[y];
         });
}
void solve()
{
    for (int j = 1; j <= n; ++ j)
    {
        int i = id[j];
        while(k[i]--)
        {
            if (keep[w[i]].size() == s/w[i])
            {
                break;
            }
            keep[w[i]].push_back(v[i]);
        }
    }
    for (int i = 1; i <= s; ++ i)
    {
        if (keep[i].empty())
        {
            continue;
        }
        for (int j = s; j >= 0; -- j)
        {
            int x = j;
            long long sum = 0;
            for (int l : keep[i])
            {
                x += i;
                sum += l;
                if (x > s)
                {
                    break;
                }
                dp[x] = max(dp[x], dp[j] + sum);
            }
        }
        for (int j = 1; j <= s; ++ j)
        {
            dp[j] = max(dp[j], dp[j - 1]);
        }
    }
    cout << dp[s];
}
int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    if (fopen(TASK".INP", "r"))
    {
        freopen(TASK".INP", "r", stdin);
        //freopen(TASK".OUT", "w", stdout);
    }
    int t = 1;
    bool typetest = false;
    if (typetest)
    {
        cin >> t;
    }
    for (int __ = 1; __ <= t; ++ __)
    {
        //cout << "Case " << __ << ": ";
        read();
        solve();
    }
}

Compilation message (stderr)

knapsack.cpp: In function 'void solve()':
knapsack.cpp:31:35: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   31 |             if (keep[w[i]].size() == s/w[i])
      |                 ~~~~~~~~~~~~~~~~~~^~~~~~~~~
knapsack.cpp: In function 'int main()':
knapsack.cpp:72:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   72 |         freopen(TASK".INP", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 12 / 12
• Subtask 2: 17 / 17
• Subtask 3: 20 / 20
• Subtask 4: 24 / 24
• Subtask 5: 27 / 27