oj.uz

Submission #956900

# Submission time Handle Problem Language Result Execution time Memory
956900 2024-04-02T16:02:45 Z Requiem Bigger segments (IZhO19_segments) C++17
0 / 100
 1 ms 2396 KB 
#include<bits/stdc++.h>
#define int long long
#define pb push_back
#define fast ios_base::sync_with_stdio(false), cin.tie(nullptr), cout.tie(nullptr);
#define MOD 1000000007
#define INF 1e18
#define fi first
#define se second
#define FOR(i,a,b) for(int i=a;i<=b;i++)
#define FORD(i,a,b) for(int i=a;i>=b;i--)
#define sz(a) ((int)(a).size())
#define endl '\n'
#define pi 3.14159265359
#define TASKNAME "segments"
template<typename T> bool maximize(T &res, const T &val) { if (res < val){ res = val; return true; }; return false; }
template<typename T> bool minimize(T &res, const T &val) { if (res > val){ res = val; return true; }; return false; }
using namespace std;
typedef pair<int,int> ii;
typedef pair<int,ii> iii;
typedef vector<int> vi;
const int MAXN = 5e5 + 9;
int n, a[MAXN], pre[MAXN];

ii dp[MAXN];

void upd(ii &a, ii b){
    if (a.fi < b.fi) a = b;
    else if (a.fi == b.fi and a.se > b.se) a = b;
}
main()
{
    fast;
    if (fopen(TASKNAME".inp","r")){
        freopen(TASKNAME".inp","r",stdin);
        freopen(TASKNAME".out","w",stdout);
    }
    cin >> n;
    for(int i = 1; i <= n; i++){
        cin >> a[i];
        pre[i] = pre[i - 1] + a[i];
    }
    dp[0] = {0, 0};
    int mx = 0;
    for(int i = 0; i <= n; i++){
        int lo = i + 1;
        int hi = n;
        int res = 0;
        while(lo <= hi){
            int mid = (lo + hi) >> 1;
            if (pre[mid] - pre[i] >= dp[i].se){
                res = mid;
                hi = mid - 1;
            }
            else lo = mid + 1;
        }
        upd(dp[res], ii(dp[i].fi + 1, pre[res] - pre[i]));
        maximize(mx, dp[i].fi);
//        cout << dp[i].fi << ' ' << dp[i].se << endl;
    }
    cout << mx << endl;
}

Compilation message

segments.cpp:30:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   30 | main()
      | ^~~~
segments.cpp: In function 'int main()':
segments.cpp:34:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   34 |         freopen(TASKNAME".inp","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~
segments.cpp:35:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   35 |         freopen(TASKNAME".out","w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2392 KB Output is correct
2 Correct 1 ms 2396 KB Output is correct
3 Correct 1 ms 2396 KB Output is correct
4 Incorrect 1 ms 2392 KB Output isn't correct
5 Halted 0 ms 0 KB -

Subtask #2
0 / 14.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2392 KB Output is correct
2 Correct 1 ms 2396 KB Output is correct
3 Correct 1 ms 2396 KB Output is correct
4 Incorrect 1 ms 2392 KB Output isn't correct
5 Halted 0 ms 0 KB -

Subtask #3
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2392 KB Output is correct
2 Correct 1 ms 2396 KB Output is correct
3 Correct 1 ms 2396 KB Output is correct
4 Incorrect 1 ms 2392 KB Output isn't correct
5 Halted 0 ms 0 KB -

Subtask #4
0 / 36.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2392 KB Output is correct
2 Correct 1 ms 2396 KB Output is correct
3 Correct 1 ms 2396 KB Output is correct
4 Incorrect 1 ms 2392 KB Output isn't correct
5 Halted 0 ms 0 KB -

Subtask #5
0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2392 KB Output is correct
2 Correct 1 ms 2396 KB Output is correct
3 Correct 1 ms 2396 KB Output is correct
4 Incorrect 1 ms 2392 KB Output isn't correct
5 Halted 0 ms 0 KB -