Cod sursa(job #3120912)

Utilizator HandoMihnea-Vicentiu Hando Data 9 aprilie 2023 12:19:20
Problema Parantezare optima de matrici Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 2.65 kb
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

#define ar array
#define vt vector
#define pq priority_queue
#define pu push
#define pub push_back
#define em emplace
#define emb emplace_back
#define mt make_tuple

#define all(x) x.begin(), x.end()
#define allr(x) x.rbegin(), x.rend()
#define allp(x, l, r) x.begin() + l, x.begin() + r
#define len(x) (int)x.size()
#define uniq(x) unique(all(x)), x.end()

using namespace std;
using namespace __gnu_pbds;

using ll = long long;
using ld = long double;
using ull = unsigned long long;

template <class T, size_t N>
void re(array <T, N>& x);
template <class T> 
void re(vt <T>& x);

template <class T> 
void re(T& x) {
    cin >> x;
}

template <class T, class... M> 
void re(T& x, M&... args) {
    re(x); re(args...);
}

template <class T> 
void re(vt <T>& x) {
    for(auto& it : x)
        re(it);
}

template <class T, size_t N>
void re(array <T, N>& x) {
    for(auto& it : x)
        re(it);
}

template <class T, size_t N>
void wr(array <T, N> x);
template <class T> 
void wr(vt <T> x);

template <class T> 
void wr(T x) {
    cout << x;
}

template <class T, class ...M>  void wr(T x, M... args) {
    wr(x), wr(args...);
}

template <class T> 
void wr(vt <T> x) {
    for(auto it : x)
        wr(it, ' ');
}

template <class T, size_t N>
void wr(array <T, N> x) {
    for(auto it : x)
        wr(it, ' ');
}

template<class T, class... M>
auto mvt(size_t n, M&&... args) {
    if constexpr(sizeof...(args) == 1)
        return vector<T>(n, args...);
    else
        return vector(n, mvt<T>(args...));
}

void set_fixed(int p = 0) {
    cout << fixed << setprecision(p);
}

void set_scientific() {
    cout << scientific;
}

inline void Open(const string Name) {
    #ifndef ONLINE_JUDGE
        (void)!freopen((Name + ".in").c_str(), "r", stdin);
        (void)!freopen((Name + ".out").c_str(), "w", stdout);
    #endif
}

void solve() {
    /* range dp */
    const ll inf = 1e18;
    int n; re(n);
    vt <ll> v(n + 1); re(v);
    auto dp = mvt<ll>(n + 10, n + 10, inf);
    for (int i = 0; i <= n; ++i) {
        dp[i][i] = 0;
        if (i - 1 >= 0 and i + 1 <= n)
            dp[i][i + 1] = v[i - 1] * v[i] * v[i + 1]; 
    }

    for (int k = 2; k < n; ++k)
        for (int i = 1; i <= n - k; ++i) {
            for (int j = i; j <= i + k - 1; ++j) {
                dp[i][i + k] = min(dp[i][i + k], 
                    dp[i][j] + dp[j + 1][i + k] + v[i - 1] * v[j] * v[i + k]);
            }
        }
    wr(dp[1][n]);
}

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

    Open("podm");

    int t = 1;
    for(;t;t--) {
        solve();
    }
    
    return 0;
}