Submission #1239414

#	Time	Username	Problem	Language	Result	Execution time	Memory
1239414		vahagng	Bigger segments (IZhO19_segments)	C++20	37 / 100	4 ms	328 KiB

segments

//----------vahagng----------//
#define _CRT_SECURE_NO_WARNINGS
#include <bits/stdc++.h>
// #include <ext/pb_ds/assoc_container.hpp>
using namespace std;
// using namespace __gnu_pbds;
 
// template <class T> using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
 
#ifndef ONLINE_JUDGE
#define dbg(x) cerr << #x <<" "; print(x); cerr << endl;
#else
#define dbg(x)
#endif
 
void print(long long t) {cerr << t;}
void print(int t) {cerr << t;}
void print(string t) {cerr << t;}
void print(char t) {cerr << t;}
void print(double t) {cerr << t;}
void print(long double t) {cerr << t;}
void print(unsigned long long t) {cerr << t;}
 
template <class T, class V> void print(pair <T, V> p);
template <class T> void print(vector <T> v);
template <class T> void print(set <T> v);
template <class T, class V> void print(map <T, V> v);
template <class T> void print(multiset <T> v);
template <class T, class V> void print(T v[],V n) {cerr << "["; for(int i = 0; i < n; i++) {cerr << v[i] << " ";} cerr << "]";}
template <class T, class V> void print(pair <T, V> p) {cerr << "{"; print(p.first); cerr << ","; print(p.second); cerr << "}";}
template <class T> void print(vector <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T> void print(set <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T> void print(multiset <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T, class V> void print(map <T, V> v) {cerr << "[ "; for (auto i : v) {print(i); cerr << " ";} cerr << "]";}
 
#define ll long long
#define all(v) v.begin(), v.end()
#define rall(v) v.rbegin(), v.rend()
#define ld long double
#define sz(v) v.size()
#define endl '\n'
 
const ll inf = 1e18, mod = 1e9+7, mod2=998244353;
 
void SetIO(string str = "") {
    if (str != "") {
        freopen((str + ".in").c_str(), "r", stdin);
        freopen((str + ".out").c_str(), "w", stdout);
    } else {
        freopen("input.txt", "r", stdin);
        freopen("output.txt", "w", stdout);
    }
}
 
void FastIO(){
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);
}
 
const int N = 3e3+10;

ll n, dp[N][2], a[N], p[N];

ll rec(int i, ll pre, int cnt){
    if(i == n+1) return cnt;
    ll ans = 0;
    ans = max(ans, rec(i+1, pre + a[i], cnt));
    ll s1 = 0;
    for(int j = i; j <= n; j++){
        s1 += a[j];
        if(s1 >= pre){
            ans = max(ans, rec(j+1, s1, cnt + 1));
            break;
        }
    }
    return ans;
}

//dp[i][0] -> maximal segments on prefix i
//dp[i][1] -> sum of the last segment

void solve(int tc){
    cin >> n;
    for(int i = 1; i <= n; i++) cin >> a[i];
    for(int i = 1; i <= n; i++){
        p[i] = p[i-1] + a[i];
    }
    // if(n <= 20){
    //     cout << rec(1, 0, 0) << endl;
    //     return;
    // }
    dp[0][0] = 0;

    for(int i = 1; i <= n; i++){
        for(int j = 1; j <= i; j++){
            if(dp[j-1][1] <= p[i] - p[j-1] && dp[i][0] <= dp[j-1][0] + 1) dp[i][0] = dp[j-1][0] + 1, dp[i][1] = p[i] - p[j-1];
        }
    }
    cout << dp[n][0] << endl;
}
 
void precalc(){
    
}
 
int main() {
    // SetIO("moocast");
    FastIO();
    int test_case = 1;
    // cin >> test_case;
    precalc();
    int cnt = 1;
    while (test_case--){
      solve(cnt++);
    }
    return 0;
}

Compilation message (stderr)

segments.cpp: In function 'void SetIO(std::string)':
segments.cpp:47:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   47 |         freopen((str + ".in").c_str(), "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
segments.cpp:48:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   48 |         freopen((str + ".out").c_str(), "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
segments.cpp:50:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   50 |         freopen("input.txt", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
segments.cpp:51:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   51 |         freopen("output.txt", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~

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