Submission #716866

#	Time	Username	Problem	Language	Result	Execution time	Memory
716866		amine_aroua	Knapsack (NOI18_knapsack)	C++17	100 / 100	160 ms	38732 KiB

knapsack

#include <bits/stdc++.h>
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
using namespace std;
#define vi vector<int>
#define vl vector<long long>
#define vs vector<string>
#define vii vector<pair<int,int>>
#define vll vector<pair<long long,long long>>
#define pb push_back
#define ll long long
#define ld long double
#define nl '\n'
#define boost ios::sync_with_stdio(false)
#define mp make_pair
#define se second
#define fi first
#define fore(i, y) for(ll i = 0; i < y; i++)
#define forr(i,x,y) for(int i = x;i<=y;i++)
#define forn(i,y,x) for(ll i = y; i >= x; i--)
#define all(v) v.begin(),v.end()
#define sz(v) v.size()
#define clr(v,k) memset(v,k,sizeof(v))
#define ub upper_bound
#define lb lower_bound

const ll MOD = 1e9 + 7;
const ll INF = 1e18 + 1;

ll gcd(ll a , ll b) {return b ? gcd(b , a % b) : a ;} // greatest common divisor (PGCD)
ll lcm(ll a , ll b) {return (a * b) / gcd(a , b);} // least common multiple (PPCM)

// HERE IS THE SOLUTION

int main()
{
    cin.tie(0);
    cout.tie(0);
    boost;
    int s , n;
    cin>>s>>n;
    vl val(n) , weight(n) , k(n);
    map<ll ,vll> weights;
    forr(i, 1 , n)
    {
        ll a , b, c;
        cin>>a>>b>>c;
        weights[b].pb({a , c});
    }
    vector<vl> dp(s+1 , vl(sz(weights)+1 , INT32_MIN));
    int i = 0;
    dp[0][0] = 0;
    for(auto p : weights)
    {
        i++;
        vll val = p.se;
        sort(val.rbegin() , val.rend());
        ll y = p.fi;
        forr(w , 0 , s)
        {
            dp[w][i] = dp[w][i-1];
            ll prev = 0;
            ll j = 0;
            ll x = 1;
            ll used = 1;
            while(x*y<=w&&j<sz(val))
            {
                int k = val[j].se , v = val[j].fi;
                if(used<=k)
                {
                    prev+=v;
                    if(dp[w - x*y][i-1]!=INT32_MIN)
                        dp[w][i] = max(dp[w][i] , dp[w - x*y][i-1]+prev);
                }
                if(used == k)
                {
                    used = 0;
                    j++;
                }
                used++;
                x++;
            }
        }
    }
    ll ans = INT32_MIN;
    fore(i , s+1)
    {
        ans = max(ans , dp[i][sz(weights)]);
    }
    cout<<ans<<nl;
}

Compilation message (stderr)

knapsack.cpp: In function 'int main()':
knapsack.cpp:66:28: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   66 |             while(x*y<=w&&j<sz(val))
      |                            ^

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