Submission #1268466

#	Time	Username	Problem	Language	Result	Execution time	Memory
1268466		herominhsteve	Knapsack (NOI18_knapsack)	C++20	0 / 100	0 ms	324 KiB

knapsack

#include <bits/stdc++.h>
#define el '\n'
#define FNAME "CSES"
#define allof(x) x.begin(),x.end()
#define allof1(x) x.begin()+1,x.end()
#define mset(x,n) memset((x),(n),sizeof(x));
using namespace std;

const long long MOD = 1e9+7;

template<class X,class Y> bool maximize(X &a,Y b){if (a<b){a=b; return true;} return false;}

void setup(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);cout.tie(0);
    if (fopen(FNAME".inp","r")){
        freopen(FNAME".inp","r",stdin);
        freopen(FNAME".out","w",stdout);
    }
}

int n, W;
vector<int> w, v, c;

void init(){
    cin >> n >> W;
    w.resize(n+1);
    v.resize(n+1);
    c.resize(n+1);
    for (int i=1;i<=n;i++) cin >> w[i];
    for (int i=1;i<=n;i++) cin >> v[i];
    for (int i=1;i<=n;i++) cin >> c[i];  // input counts
}

void sol(){
    // convert into 0/1 items
    vector<pair<int,int>> items;
    for (int i=1;i<=n;i++){
        int cnt = c[i];
        int base = 1;
        while (cnt > 0){
            int take = min(base, cnt);
            items.push_back({w[i]*take, v[i]*take});
            cnt -= take;
            base <<= 1;
        }
    }

    // 0/1 knapsack
    vector<int> dp(W+1, 0);
    for (auto [wt, val] : items){
        for (int cap=W; cap>=wt; cap--){
            maximize(dp[cap], dp[cap-wt] + val);
        }
    }

    cout << dp[W] << el;
}

int main(){
    setup();
    init();
    sol();
}

Compilation message (stderr)

knapsack.cpp: In function 'void setup()':
knapsack.cpp:17:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   17 |         freopen(FNAME".inp","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
knapsack.cpp:18:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   18 |         freopen(FNAME".out","w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

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