Submission #1319314

#	Time	Username	Problem	Language	Result	Execution time	Memory
1319314		quan123	Knapsack (NOI18_knapsack)	C++20	73 / 100	1095 ms	16160 KiB

knapsack

#include <bits/stdc++.h>
#define int long long

using namespace std;

template<typename T, typename... Args>
void print(T t) {cout << t << '\n';}
template<typename T, typename... Args>
void print(T t, Args... args) {cout << t << " "; print(args...) ;}

const int S = 2005 , MX = 1e9+7;

int dp[S];
int n , s , cnt , ans = -MX;
vector<int> v;
vector<int> w;

void file_input() {
    if (fopen("inp.txt" , "r")) {
        freopen("inp.txt" , "r" , stdin);
        freopen("out.txt" , "w" , stdout);
    }
}

signed main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    file_input();
    cin >> s >> n;
    while (n--) {
        int a , b , k , sm;
        cin >> a >> b >> k;
        sm = k;
        for (int p = 0; (k>>p) > 1; p++) {
            v.push_back(a<<p);
            w.push_back(b<<p);
            cnt++;
            sm -= (1<<p);
        }
        v.push_back(a*sm);
        w.push_back(b*sm);
        cnt++;
    }
    for (int i = 1; i < S; i++) {dp[i] = -1;}
    for (int i = 0; i < cnt; i++) {
        for (int p = s; p >= 0; p--) {
            if (dp[p] == -1) {continue;}
            if (p+w[i] > s) {continue;}
            dp[p+w[i]] = max(dp[p+w[i]] , dp[p]+v[i]);
        }
    }
    for (int p = 0; p <= s; p++) {
        ans = max(ans , dp[p]);
    }
    cout << ans;
    return 0;
}

Compilation message (stderr)

knapsack.cpp: In function 'void file_input()':
knapsack.cpp:20:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   20 |         freopen("inp.txt" , "r" , stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
knapsack.cpp:21:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   21 |         freopen("out.txt" , "w" , stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~

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