Submission #673551

#	Time	Username	Problem	Language	Result	Execution time	Memory
673551		Cutebol	Biochips (IZhO12_biochips)	C++17	100 / 100	280 ms	401664 KiB

biochips

#include <bits/stdc++.h>
 
using namespace std;
 
void fopn(string name){freopen((name+".in").c_str(),"r",stdin); freopen((name+".out").c_str(),"w",stdout);}
#define Scaramouche ios_base::sync_with_stdio(0) ; cin.tie(0) ; cout.tie(0);
//#define int long long
#define itn int
#define endl "\n"
#define ff first
#define ss second
   
const int N = 2e5 + 5 ;
const int mod = 1e9 + 7 ;
const int inf = 1e9 ;

int n , m , s , timer = 1 ;
int a[N] , p , b[N] , tin[N] ;
int dp[N][505] ;
vector <int> g[N] ;

void dfs( int v ){
	int tt = timer ;
	for ( auto to : g[v] ) dfs(to) ;
	tin[timer] = tt ;
	b[timer] = a[v] ;
	timer ++ ;
}

void solve(){
	
	cin >> n >> m ;
	for ( int i = 1 ; i <= n ; i ++ ){
		cin >> p >> a[i] ;
		if (!p) s = i ;
		else g[p].push_back(i) ;
	}
	dfs(s) ;
	for ( int i = 0 ; i <= n ; i ++ ) {
		for ( int j = 1 ; j <= m ; j ++ ) {
			dp[i][j] = -inf ;
		}
	}
	for ( int i = 1 ; i <= n ; i ++ ){
		for ( int j = 1 ; j <= m ; j ++ ){
			dp[i][j] = max ( dp[i-1][j] , dp[tin[i]-1][j-1] + b[i] ) ;
		}
	}
	cout << dp[n][m] ;
}
 
signed main(){
//  fopn("blocks") ;
    Scaramouche ;
    int t = 1 ;
//    	cin >> t ;
    while ( t -- ) solve() ; 
}

Compilation message (stderr)

biochips.cpp: In function 'void fopn(std::string)':
biochips.cpp:5:31: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
    5 | void fopn(string name){freopen((name+".in").c_str(),"r",stdin); freopen((name+".out").c_str(),"w",stdout);}
      |                        ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
biochips.cpp:5:72: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
    5 | void fopn(string name){freopen((name+".in").c_str(),"r",stdin); freopen((name+".out").c_str(),"w",stdout);}
      |                                                                 ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 100 / 100