Submission #957560

#	Time	Username	Problem	Language	Result	Execution time	Memory
957560		roadster	Knapsack (NOI18_knapsack)	C++17	29 / 100	2 ms	1368 KiB

knapsack

#include <bits/stdc++.h>
using namespace std;

using vi = vector<int>;
using vvi = vector<vector<int> >;
using pi = pair<int, int>;
using ll = long long;

#define sz(x) (int)(x).size()
#define all(x) (x).begin(), (x).end()
#define f first
#define s second
#define pb push_back

const ll MOD = 1e9 + 7;
ll expo(ll x, ll n) {
    ll res = 1LL;
    while (n) {
           if (n % 2){ res = res * x % MOD; }
        x = x * x % MOD;
        n /= 2;
    }
    return res;
}

vector<ll> factorial(int n) {
    vector<ll> fact(n + 1);
    fact[0] = 1;
    for (int i = 1; i <= n; i++) { fact[i] = fact[i - 1] * i % MOD; }
    return fact;
}

vector<ll> mod_inverse(int n, ll fact_n) {
    vector<ll> inv(n + 1);
    inv[n] = expo(fact_n, MOD - 2);
    for (int i = n; i >= 1; i--) {
        inv[i - 1] = inv[i] * i % MOD;
    }
    return inv;
}

void setIO(string s) {
    freopen((s + ".in").c_str(), "r", stdin);
    freopen((s + ".out").c_str(), "w", stdout);
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    // your code goes here
    int t, n;
    cin >> t >> n; 
    vi v(n + 1), w(n + 1), k(n + 1);
    for (int i = 1; i <= n; i++) cin >> v[i] >> w[i] >> k[i];

    vvi dp(n + 1, vi (t + 1));

    for (int i = 1; i <= n; i++) {
        vi used(t + 1);
        for (int j = 1; j <= t; j++) {
            int a = INT_MIN, b = INT_MIN, c = INT_MIN;
            a = dp[i-1][j];
            if (j - w[i] >= 0) {
                b = dp[i-1][j-w[i]] + v[i];
                if (used[j-w[i]] < k[i]) c = dp[i][j-w[i]] + v[i];
            }

            int res = max({a, b, c});

            if (res == a) {
                dp[i][j] = res;
            } else if (res == b) {
                dp[i][j] = res;
                used[j] = 1;
            } else if (res == c) {
                dp[i][j] = res;
                used[j] = used[j-w[i]] + 1;
            }
        }
    }

    int ans = 0;
    for (int i = 1; i <= t; i++) ans = max(ans, dp[n][i]);

    cout << ans << "\n";
    return 0;
}

Compilation message (stderr)

knapsack.cpp: In function 'void setIO(std::string)':
knapsack.cpp:43:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   43 |     freopen((s + ".in").c_str(), "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
knapsack.cpp:44:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   44 |     freopen((s + ".out").c_str(), "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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