Submission #959087

#	Time	Username	Problem	Language	Result	Execution time	Memory
959087		thunopro	Semiexpress (JOI17_semiexpress)	C++14	18 / 100	47 ms	2500 KiB

semiexpress

#include<bits/stdc++.h>
using namespace std ; 
#define maxn 200009 
#define ll long long 
#define fi first 
#define se second 
#define pb push_back 
#define left id<<1
#define right id<<1|1 
#define _lower(x) lower_bound(v.begin(),v.end(),x)-v.begin()+1 
//#define TIME (1.0*clock()/TIME_PERS_SEC) 
#define re exit(0); 

const int mod = 1e9+7 ; 
const int INF = 1e9+1e8 ; 

typedef vector<int> vi ; 
typedef pair<int,int> pii ; 
typedef vector<pii> vii ; 

void add ( int &a , int b ) 
{
	a += b ; 
	if ( a >= mod ) a -= mod ; 
	if ( a < 0 ) a += mod ; 
}

template < typename T > void chkmin ( T &a , T b ) { if ( a > b ) a = b ;} 
template < typename T > void chkmax ( T &a , T b ) { if ( a < b ) a = b ;} 

void rf () 
{
	freopen ("bai1.inp","r",stdin) ; 
}

mt19937 rng (time(0)) ; 

int _pow ( int a , int n ) 
{
	if ( n == 0 ) return 1 ; 
	int res = _pow (a,n/2) ; 
	if ( n % 2 ) return 1ll*res*res%mod*a%mod ; 
	else return 1ll*res*res%mod ; 
}

int n , m , k , A , B , C ; 
int express [maxn] , pos_express [maxn] ; 
ll TIME ; 
int dp [maxn] ; 
void sub1 () 
{
	int res = 0 ; 
	for ( int one = 1 ; one <= n ; one ++ ) for ( int two = one+1 ; two <= n ; two ++ ) 
	{
		if ( pos_express [one] == 0 && pos_express [two] == 0 ) 
		{
			fill (dp+1,dp+n+1,INF) ; 
			for ( int i = 1 ; i <= n ; i ++ ) 
			{
				if ( i == 1 ) dp [i] = 0 ; 
				else chkmin (dp[i],dp[i-1]+A) ; 
				if ( pos_express[i] != 0 ) 
				{
					if ( pos_express[i] < m ) 
					{
						int nxt = express[pos_express[i]+1] ;
						chkmin (dp[nxt],dp[i]+(nxt-i)*B) ; 
					}
					if ( one > i ) 
					{
						int nxt = one ; 
						chkmin (dp[nxt],dp[i]+(nxt-i)*C) ; 
					}
					if ( two > i ) 
					{
						int nxt = two ; 
						chkmin (dp[nxt],dp[i]+(nxt-i)*C) ; 
					}
				}				
			}
			int ans = 0 ; 
			for ( int i = 2 ; i <= n ; i ++ ) if ( dp [i] <= TIME ) ans ++ ; 
			chkmax(res,ans) ; 
		}
	}
	cout << res ; re 
}
int main ()
{
	ios_base::sync_with_stdio(0); 
	cin.tie(0);cout.tie(0); 
//	rf () ; 
	cin >> n >> m >> k ; 
	cin >> A >> B >> C >> TIME ; 
	for ( int i = 1 ; i <= m ; i ++ ) 
	{
		cin >> express [i] ; 
		pos_express [express[i]] = i ; 
	}
	if ( n <= 300 && k == m+2 ) sub1 () ; 
}

Compilation message (stderr)

semiexpress.cpp: In function 'void rf()':
semiexpress.cpp:33:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   33 |  freopen ("bai1.inp","r",stdin) ;
      |  ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 18 / 18
• Subtask 2: 0 / 30
• Subtask 3: 0 / 52