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Submission #164412

# Submission time Handle Problem Language Result Execution time Memory
164412 2019-11-20T13:33:29 Z Lawliet Chase (CEOI17_chase) C++14
100 / 100
 1683 ms 363112 KB 
#include <bits/stdc++.h>

using namespace std;
typedef long long int lli;

const int MAXK = 110;
const int MAXN = 100010;

int n, k;

int v[MAXN];
int maxDP[MAXN][MAXK][2];

lli ans;

lli sum[MAXN];
lli dp[MAXN][MAXK];

vector< int > adj[MAXN];

void DFSCalculate(int cur, int p)
{
	for(int i = 0 ; i < adj[cur].size() ; i++)
	{
		int viz = adj[cur][ i ];

		if( viz == p ) continue;

		sum[ cur ] += v[ viz ];
		DFSCalculate( viz , cur );
	}

	for(int j = 1 ; j <= k ; j++)
	{
		for(int i = 0 ; i < adj[cur].size() ; i++)
		{
			int viz = adj[cur][ i ];

			if( viz == p ) continue;

			if( dp[viz][j] > dp[ maxDP[cur][j][1] ][ j ] ) maxDP[ cur ][ j ][1] = viz;
			if( dp[ maxDP[cur][j][1] ][ j ] > dp[ maxDP[cur][j][0] ][ j ]) 
				swap( maxDP[ cur ][ j ][0] , maxDP[ cur ][ j ][1] );
		}

		dp[ cur ][ j ] = dp[ maxDP[cur][j - 1][0] ][ j - 1 ] + sum[ cur ];
		dp[ cur ][ j ] = max( dp[ cur ][ j ] , dp[ maxDP[cur][j][0] ][ j ] );
	}
}

void DFSRotate(int cur, int p)
{
	ans = max( ans , dp[cur][k] );

	for(int i = 0 ; i < adj[cur].size() ; i++)
	{
		int viz = adj[cur][ i ];

		if( viz == p ) continue;

		vector< lli > oldDPCur;
		vector< lli > oldDPViz;

		vector< int > oldMaxDPCur[2];
		vector< int > oldMaxDPViz[2];

		lli oldSumCur = sum[ cur ];
		lli oldSumViz = sum[ viz ];

		for(int j = 0 ; j <= k ; j++)
		{
			oldDPCur.push_back( dp[cur][j] );
			oldDPViz.push_back( dp[viz][j] );

			for(int p = 0 ; p < 2 ; p++)
			{
				oldMaxDPCur[p].push_back( maxDP[cur][j][p] );
				oldMaxDPViz[p].push_back( maxDP[viz][j][p] );
			}
		}

		sum[ cur ] -= v[ viz ];
		sum[ viz ] += v[ cur ];

		for(int j = 1 ; j <= k ; j++)
		{
			lli newDPCur = 0;

			if( maxDP[ cur ][ j - 1 ][0] == viz ) newDPCur = dp[ maxDP[cur][j - 1][1] ][ j - 1 ] + sum[ cur ];
			else newDPCur = dp[ maxDP[cur][j - 1][0] ][ j - 1 ] + sum[ cur ];

			if( maxDP[ cur ][ j ][0] == viz ) newDPCur = max( newDPCur , dp[ maxDP[cur][j][1] ][ j ] );
			else newDPCur = max( newDPCur , dp[ maxDP[cur][j][0] ][ j ] );

			dp[ cur ][ j ] = newDPCur;
		}

		for(int j = 1 ; j <= k ; j++)
		{
			if( dp[cur][j] > dp[ maxDP[viz][j][1] ][ j ] ) maxDP[ viz ][ j ][1] = cur;
			if( dp[ maxDP[viz][j][1] ][ j ] > dp[ maxDP[viz][j][0] ][ j ]) 
				swap( maxDP[ viz ][ j ][0] , maxDP[ viz ][ j ][1] );

			dp[ viz ][ j ] = max( dp[ viz ][ j ] , dp[ maxDP[viz][j][0] ][ j ] );
			dp[ viz ][ j ] = max( dp[ viz ][ j ] , dp[ maxDP[viz][j - 1][0] ][ j - 1 ] + sum[ viz ]);
		}

		DFSRotate( viz , cur );

		sum[ cur ] = oldSumCur;
		sum[ viz ] = oldSumViz;

		for(int j = 0 ; j <= k ; j++)
		{
			dp[cur][j] = oldDPCur[j];
			dp[viz][j] = oldDPViz[j];

			for(int p = 0 ; p < 2 ; p++)
			{
				maxDP[cur][j][p] = oldMaxDPCur[p][j];
				maxDP[viz][j][p] = oldMaxDPViz[p][j];
			}
		}
	}
}

int main()
{
	scanf("%d %d",&n,&k);

	for(int i = 1 ; i <= n ; i++)
		scanf("%d",&v[i]);

	for(int i = 1 ; i < n ; i++)
	{
		int U, V;
		scanf("%d %d",&U,&V);

		adj[ U ].push_back( V );
		adj[ V ].push_back( U );
	}

	DFSCalculate( 1 , 0 );
	DFSRotate( 1 , 0 );

	printf("%lld\n",ans);
}

Compilation message

chase.cpp: In function 'void DFSCalculate(int, int)':
chase.cpp:23:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0 ; i < adj[cur].size() ; i++)
                  ~~^~~~~~~~~~~~~~~~~
chase.cpp:35:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int i = 0 ; i < adj[cur].size() ; i++)
                   ~~^~~~~~~~~~~~~~~~~
chase.cpp: In function 'void DFSRotate(int, int)':
chase.cpp:55:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0 ; i < adj[cur].size() ; i++)
                  ~~^~~~~~~~~~~~~~~~~
chase.cpp: In function 'int main()':
chase.cpp:129:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d %d",&n,&k);
  ~~~~~^~~~~~~~~~~~~~~
chase.cpp:132:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d",&v[i]);
   ~~~~~^~~~~~~~~~~~
chase.cpp:137:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d %d",&U,&V);
   ~~~~~^~~~~~~~~~~~~~~

Subtask #1
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 2680 KB Output is correct
2 Correct 4 ms 2680 KB Output is correct
3 Correct 9 ms 2708 KB Output is correct
4 Correct 4 ms 2680 KB Output is correct
5 Correct 5 ms 2728 KB Output is correct
6 Correct 4 ms 2680 KB Output is correct

Subtask #2
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 2680 KB Output is correct
2 Correct 4 ms 2680 KB Output is correct
3 Correct 9 ms 2708 KB Output is correct
4 Correct 4 ms 2680 KB Output is correct
5 Correct 5 ms 2728 KB Output is correct
6 Correct 4 ms 2680 KB Output is correct
7 Correct 28 ms 6520 KB Output is correct
8 Correct 8 ms 4856 KB Output is correct
9 Correct 8 ms 4472 KB Output is correct
10 Correct 15 ms 4472 KB Output is correct
11 Correct 10 ms 4472 KB Output is correct
12 Correct 9 ms 4472 KB Output is correct

Subtask #3
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 1555 ms 359480 KB Output is correct
2 Correct 1513 ms 358660 KB Output is correct
3 Correct 1149 ms 180264 KB Output is correct
4 Correct 418 ms 180332 KB Output is correct
5 Correct 1291 ms 180572 KB Output is correct
6 Correct 1264 ms 180472 KB Output is correct
7 Correct 1229 ms 180732 KB Output is correct

Subtask #4
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 2680 KB Output is correct
2 Correct 4 ms 2680 KB Output is correct
3 Correct 9 ms 2708 KB Output is correct
4 Correct 4 ms 2680 KB Output is correct
5 Correct 5 ms 2728 KB Output is correct
6 Correct 4 ms 2680 KB Output is correct
7 Correct 28 ms 6520 KB Output is correct
8 Correct 8 ms 4856 KB Output is correct
9 Correct 8 ms 4472 KB Output is correct
10 Correct 15 ms 4472 KB Output is correct
11 Correct 10 ms 4472 KB Output is correct
12 Correct 9 ms 4472 KB Output is correct
13 Correct 1555 ms 359480 KB Output is correct
14 Correct 1513 ms 358660 KB Output is correct
15 Correct 1149 ms 180264 KB Output is correct
16 Correct 418 ms 180332 KB Output is correct
17 Correct 1291 ms 180572 KB Output is correct
18 Correct 1264 ms 180472 KB Output is correct
19 Correct 1229 ms 180732 KB Output is correct
20 Correct 1233 ms 181472 KB Output is correct
21 Correct 406 ms 181496 KB Output is correct
22 Correct 1330 ms 181664 KB Output is correct
23 Correct 422 ms 181532 KB Output is correct
24 Correct 1229 ms 181724 KB Output is correct
25 Correct 1102 ms 181588 KB Output is correct
26 Correct 1683 ms 363064 KB Output is correct
27 Correct 1543 ms 363112 KB Output is correct