Submission #498356

#	Time	Username	Problem	Language	Result	Execution time	Memory
498356		vinnipuh01	Sure Bet (CEOI17_sure)	C++17	100 / 100	203 ms	8524 KiB

sure

#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 double long double
 
using namespace std;
 
const long long oo = 1000000000000000000;
 
double  sum, ans = 0, mx = 0, mn, num, pos;
 
 
/*
    ViHHiPuh
 
   (( `'-""``""-'` ))
     )-__-_.._-__-(
   / --- (o _ o) --- \
   \ .-* ( .0. ) *-. /
   _'-. ,_ '=' _, .-'_
  / `;#'#'# - #'#'#;` \
 \_)) -----'#'----- ((_/
      # --------- #
  '# ------- ------ #'
  /..-'# ------- #'-.\
  _\...-\'# -- #'/-.../_
  ((____)- '#' -(____))
 
 
    cout << fixed << setprecision(6) << x;
 
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
 
    freopen ( "sum.in", "r", stdin )
*/
 
int n;
double a[ 100001 ], b[ 100001 ];
vector <double> v, vv;
 
double f( int mask, int o, double sum, double ans, double col ) {
	double mxx = min( sum - col, ans - col );
	for ( int i = o; i < n; i ++ ) {
		if ( !( mask & ( 1 << i ) ) ) {
			mask |= ( 1 << i );
			col ++;
			sum += a[ i ];
			mxx = max( mxx, f( mask, i + 1, sum, ans, col ) );
			sum -= a[ i ];
			ans += b[ i ];
			mxx = max( mxx, f( mask, i + 1, sum, ans, col ) );
			col --;
			ans -= b[ i ];
			col += 2;
			ans += b[ i ];
			sum += a[ i ];
			mxx = max( mxx, f( mask, i + 1, sum, ans, col ) );
			col -= 2;
			ans -= b[ i ];
			sum -= a[ i ];
			mask ^= ( 1 << i );
		}
	}
	return mxx;
}
 
double p[ 100001 ];
 
double f( int x ) {
	return min( sum - pos, p[ x ] - pos );
}
 
int main () {
	cin >> n;
	for ( int i = 1; i <= n; i ++ ) {
		cin >> a[ i ] >> b[ i ];
		v.push_back( a[ i ] );
		vv.push_back( b[ i ] );
	}
	sort( v.begin(), v.end() );
	sort( vv.begin(), vv.end() );
	reverse( v.begin(), v.end() );
	reverse( vv.begin(), vv.end() );
	for ( int i = 0; i < vv.size(); i ++ )
		p[ i + 1 ] = vv[ i ] + p[ i ];
	sum = num = ans = mx = 0;
	int l, r, mid2, mid1;
	for ( int i = 0; i < v.size(); i ++ ) {
		sum += v[ i ];
		ans = i + 1;
		mx = max( mx, min( sum - ans, -ans ) );
		l = 1;
		r = vv.size();
		while ( r - l > 2 ) {
			mid1 = l + ( r - l ) / 3;
			mid2 = r - ( r - l ) / 3;
			pos = mid1 + i + 1;
			ans = f( mid1 );
			pos = mid2 + i + 1;
			mn = f( mid2 );
			if ( ans < mn )
				l = mid1;
			else
				r = mid2;
		}
		pos = r + i + 1;
		ans = f( r );
		pos = i + l + 1;
		mn = f( l );
		if ( ans >= mn )
			l = r;
		pos = ( r - 1 ) + i + 1;
		ans = f( r - 1 );
		pos = l + i + 1;
		mn = f( l );
		if ( ans >= mn )
			l = r - 1;
		pos = l + i + 1;
		mx = max( mx, f( l ) );
	}
	cout << fixed << setprecision(4) << mx;
}

Compilation message (stderr)

sure.cpp: In function 'int main()':
sure.cpp:93:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long double>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   93 |  for ( int i = 0; i < vv.size(); i ++ )
      |                   ~~^~~~~~~~~~~
sure.cpp:97:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long double>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   97 |  for ( int i = 0; i < v.size(); i ++ ) {
      |                   ~~^~~~~~~~~~

• Subtask 1: 20 / 20
• Subtask 2: 40 / 40
• Subtask 3: 40 / 40