Submission #334202

#	Time	Username	Problem	Language	Result	Execution time	Memory
334202		BeanZ	Bigger segments (IZhO19_segments)	C++14	37 / 100	90 ms	71020 KiB

segments

// I_Love_LPL
#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define endl '\n'
const int N = 3e3 + 5;
long long mod = 1e9 + 7;
const int lim = 5e5;
const int lg = 20;
const int base = 311;
const long double eps = 1e-6;
ll a[N], sum[N], dp[N][N];
int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    if (fopen("test.inp", "r")){
        freopen("test.inp", "r", stdin);
        freopen("test.out", "w", stdout);
    }
    ll n;
    cin >> n;
    for (int i = 1; i <= n; i++) cin >> a[i], sum[i] = sum[i - 1] + a[i];
    for (int i = 1; i <= n; i++){
        for (int j = 1; j <= n; j++){
            dp[i][j] = -1e9;
        }
    }
    for (int i = 1; i <= n; i++) dp[1][i] = 1;
    for (int i = 2; i <= n; i++){
        ll best = -1e9;
        ll l = i - 1;
        for (int j = i; j <= n; j++){
            ll tot = sum[j] - sum[i - 1];
            while (l > 0 && (sum[i - 1] - sum[l - 1]) <= tot){
                best = max(best, dp[l][i - 1]);
                l--;
            }
            dp[i][j] = best + 1;
        }
    }
    //cout << dp[1][1] << " " << dp[2][3] << endl;
    ll ans = 0;
    for (int i = 1; i <= n; i++){
        ans = max(ans, dp[i][n]);
    }
    cout << ans;
}
/*
Ans:

Out:
*/

Compilation message (stderr)

segments.cpp: In function 'int main()':
segments.cpp:17:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   17 |         freopen("test.inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
segments.cpp:18:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   18 |         freopen("test.out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

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