94 lines
2.1 KiB
C++
94 lines
2.1 KiB
C++
#include<cstdio>
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#include<cstring>
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#include<algorithm>
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using namespace std;
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#define min(a,b) a>b?b:a
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#pragma comment(linker,"/STACK:1000000000,1000000000")
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const int maxn = 10010;
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const int INF = 1000000000;
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int dp[maxn][110];
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int sum[maxn],sumd[maxn];
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int head[maxn];
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struct Edge{
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int v,next;
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}edge[2*maxn];int N,L,E;
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void add_edge(int a,int b)
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{
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edge[E].v=b;
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edge[E].next=head[a];
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head[a]=E++;
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}
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void dfs(int u,int fa)
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{
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int i,j,k,v;
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sum[u]=1;sumd[u]=0;
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fill(dp[u],dp[u]+L+1,INF);
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for(i=head[u];i!=-1;i=edge[i].next)
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{
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v=edge[i].v;
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if(v==fa) continue;
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dfs(v,u);
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sumd[u]+=sumd[v]+sum[v];
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sum[u]+=sum[v];
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}
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dp[u][0]=sumd[u];
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for(i=head[u];i!=-1;i=edge[i].next)
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{
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v=edge[i].v;
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if(v==fa) continue;
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for(j=1;j<=L;j++)
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dp[u][j]=min(dp[u][j],dp[v][j-1]+sumd[u]-sumd[v]-sum[v]);
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}
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}
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int ans[maxn];
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void solve(int u,int fa)
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{
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int i,a,v;
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if(u==0) ans[u]=sumd[0];
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else ans[u]=N-sum[u]+sumd[fa]-sum[u];
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int tmp[110];
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fill(tmp,tmp+L+1,INF);
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int mi=INF;
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for( i=head[u];i!=-1;i=edge[i].next)
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{
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v=edge[i].v;
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if(v==fa) continue;
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for( a=0;a<=L-2;a++)
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mi=min(mi,tmp[L-2-a]+dp[v][a]-sumd[v]-sum[v]);
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for( a=0;a<=L-1;a++)
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{
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tmp[a]=min(tmp[a],dp[v][a]-sumd[v]-sum[v]);
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if(a) tmp[a]=min(tmp[a],tmp[a-1]);
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}
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}
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mi=min(mi,tmp[L-1]);
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sumd[u]=ans[u];
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ans[u]+=mi;
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for(i=head[u];i!=-1;i=edge[i].next)
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{
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v=edge[i].v;
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if(v==fa) continue;
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solve(v,u);
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}
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}
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int main()
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{
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int i,j,k,a,b;
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while(scanf("%d%d",&N,&L),(N||L))
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{
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if(N==1) {puts("0");continue;}
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E=0;
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memset(head,-1,sizeof(head));
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for(i=0;i<N-1;i++)
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{
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scanf("%d%d",&a,&b);
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add_edge(a,b);
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add_edge(b,a);
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}
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dfs(0,0);
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solve(0,0);
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printf("%d\n",*min_element(ans,ans+N));
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}
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return 0;
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}
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