Submission #162889

#	Time	Username	Problem	Language	Result	Execution time	Memory
162889		abacaba	Bigger segments (IZhO19_segments)	C++14	13 / 100	2 ms	380 KiB

segments

#include <iostream>
#include <string>
#include <unordered_map>
#include <cstring>
#include <chrono>
#include <vector>
#include <map>
#include <random>
#include <set>
#include <algorithm>
#include <math.h>
#include <cstdio>
#include <stdio.h>
#include <queue>
#include <bitset>
#include <cstdlib>
#include <deque>
#include <cassert>
#include <stack>
using namespace std;

#define int long long

const int inf = 2e9;
const int mod = 1e9 + 7;
const int N = 5e5 + 15;
int n, m, a[N], p[N], maxp[N], dp[N], sumback[N];

main() {
    ios_base::sync_with_stdio(0); cout.tie(0); cin.tie(0);
    cin >> n;
    for(int i = 1; i <= n; ++i) {
        cin >> a[i];
        p[i] = p[i-1] + a[i];
        maxp[i] = max(maxp[i-1], p[i]);
    }
    for(int i = 1; i <= n; ++i) {
        dp[i] = 1;
        int l = 1, r = i - 1;
        while(l <= r) {
            int mid = l + r >> 1;
            if(2 * p[mid] - p[sumback[mid]] <= p[i]) {
                if(dp[mid] + 1 >= dp[i]) {
                    sumback[i] = max(sumback[i], mid);
                    dp[i] = dp[mid] + 1;
                }
                l = mid + 1;
            }
            else
                r = mid - 1;
        }
    }
    cout << dp[n] << endl;
    return 0;
}

Compilation message (stderr)

segments.cpp:29:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
 main() {
      ^
segments.cpp: In function 'int main()':
segments.cpp:41:25: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
             int mid = l + r >> 1;
                       ~~^~~

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