Submission #1043190

#	Time	Username	Problem	Language	Result	Execution time	Memory
1043190		vjudge1	Knapsack (NOI18_knapsack)	C++17	73 / 100	226 ms	262144 KiB

knapsack

#include<bits/stdc++.h>
#define ll long long
#define ull unsigned long long
#define bip(i) __builtin_popcount(i)
#define gb(i,j) ((i>>j)&1)
#define se second
#define fi first
using namespace std;

const int N=2005;
int n , S;
ll f[2][N] , res;
vector<pair<int,int>>vec[N] , prc;

int main()
{
    cin.tie(0) -> sync_with_stdio(false);
    cin >> S >> n;
    for( int i=1 ; i<=n ; i++ ){
        int v , w , fre;
        cin >> v >> w >> fre;
        vec[w].push_back({v , fre});
    }
    prc.push_back({0,0});
    for( int i=1 ; i<=S ; i++ ) // weight
        if(vec[i].size()){
            sort(vec[i].begin() , vec[i].end() , greater<pair<int,int>>() );
            for( auto [val , fr]: vec[i] ){
                int tmp=0 , ch=0;
                for( int k=1 ; k<=fr ; k++ ){
                    tmp+=i;
                    if(tmp<=S)
                        prc.push_back({val , i});
                    else{
                        ch=1;
                        break;
                    }
                }
                if(ch)break;
            }
        }
    for( int i=1 ; i<prc.size() ; i++ ){
        int val = prc[i].fi , wei = prc[i].se;
        for( int j=S ; j>=0 ; j-- )f[i%2][j]=f[(i-1)%2][j]; // truong hop ko chon i
        for( int j=S ; j>=0 ; j-- )if(j>=wei){
            f[i%2][j] = max( f[i%2][j] , f[(i-1)%2][j-wei]+val ); // truong hop chon i
            res = max( res , f[i%2][j] );
        }else break;
    }
    cout << res;
}

Compilation message (stderr)

knapsack.cpp: In function 'int main()':
knapsack.cpp:42:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   42 |     for( int i=1 ; i<prc.size() ; i++ ){
      |                    ~^~~~~~~~~~~

• Subtask 1: 12 / 12
• Subtask 2: 17 / 17
• Subtask 3: 20 / 20
• Subtask 4: 24 / 24
• Subtask 5: 0 / 27