Submission #944766

#	Time	Username	Problem	Language	Result	Execution time	Memory
944766		Baizho	Bigger segments (IZhO19_segments)	C++17	27 / 100	36 ms	20312 KiB

segments

    #include <bits/stdc++.h>
    using namespace std;
    #include <ext/pb_ds/assoc_container.hpp>
    #include <ext/pb_ds/tree_policy.hpp>
    using namespace __gnu_pbds;
      
    #define ordered_set tree<int, null_type,less_equal<int>, rb_tree_tag,tree_order_statistics_node_update>
     
    // #pragma GCC optimize("Ofast,unroll-loops,fast-math")
    // #pragma GCC target("popcnt,sse3,avx")
     
     
    typedef long long ll;
    typedef unsigned long long ull;
    typedef long double ld;
    typedef pair<ll,ll> pll;
     
    #define sz size()
    #define ff first
    #define ss second
    #define all(a) a.begin(),a.end()
    #define pb push_back
     
    const int mod = ll(1e9)+7; //(b + (a%b)) % b (to mod -1%(10^9+7) correctly in c++ its -1 but its suppose to be 10^9+6
    const ll MOD = 998244353;  // (a%mod)*(binpow(b,mod-2,mod) = (a/b)%mod
    const int N = ll(5e5)+100;
    const int M = ll(2e5) + 100;
    const long long inf = 5e18;
    //const long double eps = 1e-15L;
     
    ll lcm(ll a, ll b) { return (a / __gcd(a,b))*b; }
     
    ll binpow(ll a, ll b, ll m) { ll res=1; a %= m; while(b>0){ if(b&1)res=(res * a) % m; a=(a * a) % m; b/=2; } return res%m;}
     
    void Freopen(string Key){ freopen((Key+".in").c_str(), "r", stdin); freopen((Key+".out").c_str(), "w", stdout); }

    ll n, a[N], pr[N], dp[505][505];

    ll getsum(ll l, ll r) {
        return pr[r] - pr[l - 1];
    }

    void Baizho() {
        cin>>n;
        for(int i = 1; i <= n; i ++) {
            for(int j = 1; j <= n; j ++) dp[i][j] = -inf;
            cin>>a[i];
            pr[i] = pr[i - 1] + a[i];
            dp[i][i] = 1;
        }
        for(int i = 2; i <= n; i ++) {
            for(int j = 1; j < i; j ++) {
                // takes suffix i - j + 1 ... i
                int prev = i - j;
                for(int k = 1; k <= prev; k ++) {
                    if(getsum(prev - k + 1, prev) <= getsum(prev + 1, i)) dp[i][j] = max(dp[i][j], dp[prev][k] + 1);
                }
            }
        }
        ll ans = 0;
        for(int i = 1; i <= n; i ++) ans = max(ans, dp[n][i]);
        cout<<ans;
    }
     
    signed main() {     
    //  Freopen("nondec");
        ios_base::sync_with_stdio(false);   
        cin.tie(0);cout.tie(0); 
        // precalc();
        
        int ttt = 1;
       // cin>>ttt;
     
        for(int i=1; i<=ttt; i++) {Baizho(); }
    }

Compilation message (stderr)

segments.cpp: In function 'void Freopen(std::string)':
segments.cpp:35:38: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   35 |     void Freopen(string Key){ freopen((Key+".in").c_str(), "r", stdin); freopen((Key+".out").c_str(), "w", stdout); }
      |                               ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
segments.cpp:35:80: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   35 |     void Freopen(string Key){ freopen((Key+".in").c_str(), "r", stdin); freopen((Key+".out").c_str(), "w", stdout); }
      |                                                                         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 13 / 13
• Subtask 2: 14 / 14
• Subtask 3: 0 / 10
• Subtask 4: 0 / 36
• Subtask 5: 0 / 27