组队赛的时候的一道题,那个时候想了一下感觉dp不怎么好写呀,现在写了出来,交上去过了,但是我觉得我还是应该WA的呀,因为总感觉dp的不对。
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54 |
#pragma warning(disable:4996) #include<iostream> #include<cstdio> #include<algorithm> #include<cstring> #include<string> #include<vector> #define maxn 150 using
namespace std; struct
Edge { int
v, w; Edge( int
vi, int
wi) :v(vi), w(wi){} Edge(){} }; vector<Edge> G[maxn]; int
n, q; int
dp[maxn][maxn]; int
tmp[maxn]; void
dfs( int
u, int
fa) { for
( int i = 0; i < G[u].size(); i++){ int
v = G[u][i].v, w = G[u][i].w; if
(v == fa) continue ; dfs(v, u); memcpy (tmp, dp[u], sizeof (dp[u])); for
( int k = q; k >= 0; k--){ for
( int j = k - 1; j >= 0; j--){ dp[u][k] = max(dp[u][k], dp[v][j] + tmp[k-1- j] + w); } } } } int
main() { while
(cin >> n >> q) { for
( int i = 0; i <= n; i++) G[i].clear(); int
ui, vi, wi; for
( int i = 0; i < n - 1; i++){ scanf ( "%d%d%d" , &ui, &vi, &wi); G[ui].push_back(Edge(vi, wi)); G[vi].push_back(Edge(ui, wi)); } memset (dp, 0, sizeof (dp)); dfs(1, -1); cout << dp[1][q] << endl; } return
0; } |
URAL1018 Binary Apple Tree(树dp),布布扣,bubuko.com
URAL1018 Binary Apple Tree(树dp)
原文:http://www.cnblogs.com/chanme/p/3631969.html