Submission #497715

#	Time	Username	Problem	Language	Result	Execution time	Memory
497715		vinnipuh01	Bigger segments (IZhO19_segments)	C++17	0 / 100	1 ms	204 KiB

segments

#include <iostream>
#include <bits/stdc++.h>
#include <cmath>
#include <algorithm>
#include <vector>
#include <deque>
#include <set>
#include <stack>
#include <string>
#include <map>
#include <queue>
#define int long long
 
using namespace std;
 
const long long oo = 1000000000000000000;
 
long long sum, ans = 0, mx = 0, mn = 1000000000, num, pos;
 
 
/*
    ViHHiPuh
 
   (( `'-""``""-'` ))
     )-__-_.._-__-(
   / --- (o _ o) --- \
   \ .-* ( .0. ) *-. /
   _'-. ,_ '=' _, .-'_
  / `;#'#'# - #'#'#;` \
 \_)) -----'#'----- ((_/
      # --------- #
  '# ------- ------ #'
  /..-'# ------- #'-.\
  _\...-\'# -- #'/-.../_
  ((____)- '#' -(____))
 
 
    cout << fixed << setprecision(6) << x;
 
 
    freopen ( "sum.in", "r", stdin )
*/

pair<int, int> dp[ 500001 ];
int p[ 500001 ];

main () {
	int n;
	cin >> n;
	int a[ n + 1 ];
	for ( int i = 1; i <= n; i ++ ) {
		cin >> a[ i ];
		p[ i ] = p[ i - 1 ] + a[ i ];
	}
	int l, r, mid;
	for ( int i = 1; i <= n; i ++ ) {
		dp[i].second = max(dp[i].second, dp[i -1].second);
		l = i;
		r = n;
		while ( r > l ) {
			mid = ( l + r ) / 2;
			if ( p[ mid ] >= 2 * p[ i ] - p[ dp[ i ].second ] )
				r = mid;
			else
				l = mid + 1;
		}
		dp[ l ] = max( dp[ l ], { dp[ i ].first + 1, i } );
	}
	cout << dp[ n ].first;
}

// p[mid] - p[ i - 1 ] >= p[ i - 1 ] - p[ dp[ i - 1 ].second ]   

Compilation message (stderr)

segments.cpp:47:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   47 | main () {
      | ^~~~

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