Submission #1069079

#	Time	Username	Problem	Language	Result	Execution time	Memory
1069079		vjudge1	Knapsack (NOI18_knapsack)	C++17	100 / 100	75 ms	6604 KiB

knapsack

#include <bits/stdc++.h>
#define int long long
using namespace std;
#define f first
#define s second
typedef pair<int,int> pii;
typedef tuple<int, int, int> iii;
int mod = (int)1e9 + 7; 
int  lt(int l, int r, function<bool(int x)> f)
{
    l--;
    while(l < r)
    {
        int m = l + (r - l + 1) / 2;
        if(f(m)) r = m;
        else l = m + 1;
    }
    return l;
}
int pw(int a, int b)
{
    int ans = 1;
    while(b > 0)
    {
        if(b & 1) ans *= a;
        ans %= mod;
        a *= a;
        a %= mod;
        b >>= 1;
    }
    return ans;
}
int inverse(int x)
{
    return pw(x, mod - 2); 
}
void solve()
{
    int s, n; cin >> s >> n;
    int dp[s + 1] = {0};
    bool pro[s + 1] = {false};
    pro[0] = true;
    int mp[2001]; 
    for(int x = 1; x < 2001; x++) mp[x] = s/x;
    vector<pii> choose;
    vector<iii> a;
    for(int x = 0; x < n; x++)
    {
        int v, w, k; cin >> v >> w >> k;
        a.push_back({v, w, k});
    }
    sort(a.rbegin(), a.rend());
    for(iii t : a)
    {
        int v = get<0>(t);
        int w = get<1>(t);
        int k = get<2>(t);
        if(mp[w] >= k)
        {
            for(int x = 0; x < k; x++) choose.push_back({v, w});
            mp[w] -= k;
        }
        else
        {
            for(int x = 0; x < mp[w]; x++) choose.push_back({v, w});
            mp[w] = 0;
        }
    }
    int mx = 0;
    for(pii p : choose)
    {
        //cout << p.f << " " << p.s << "\n";
        for(int x = s; x >= 0; x--)
        {
            if(x - p.s >= 0)
            {
                if(pro[x - p.s])
                {
                    pro[x] = true;
                    dp[x] = max(dp[x], dp[x - p.s] + p.f);
                    mx = max(mx, dp[x]);
                }
            }
        }
    }
    cout << mx;
}
signed main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0), cout.tie(0);
	//freopen("wormsort.in", "r", stdin);
	//freopen("wormsort.out", "w", stdout);
    int t = 1;
    //cin >> t;
    while(t--)
    {
        solve();
    }
    return 0;
}

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