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　　然后顺利WA了……没想通为什么……

　　实际上不用拆的，直接建就可以S->i (INF,0)、 i->T (u[i],0)、 i->i+1 (s,m) 就连这三种边就行了= =

 1 /**************************************************************
 2     Problem: 2424
 3     User: Tunix
 4     Language: C++
 5     Result: Accepted
 6     Time:0 ms
 7     Memory:7136 kb
 8 ****************************************************************/
 9
10 //BZOJ 2424
11 #include<cmath>
12 #include<vector>
13 #include<cstdio>
14 #include<cstring>
15 #include<cstdlib>
16 #include<iostream>
17 #include<algorithm>
18 #define rep(i,n) for(int i=0;i<n;++i)
19 #define F(i,j,n) for(int i=j;i<=n;++i)
20 #define D(i,j,n) for(int i=j;i>=n;--i)
21 #define pb push_back
22 #define CC(a,b) memset(a,b,sizeof(a))
23 using namespace std;
24 int getint(){
25     int v=0,sign=1; char ch=getchar();
26     while(!isdigit(ch)) {if(ch==‘-‘) sign=-1; ch=getchar();}
27     while(isdigit(ch))  {v=v*10+ch-‘0‘; ch=getchar();}
28     return v*sign;
29 }
30 const int N=250,M=250000,INF=~0u>>2;
31 const double eps=1e-8;
32 /*******************template********************/
33 int n,m,size,ans;
34 struct edge{int from,to,v,c;};
35 struct Net{
36     edge E[M];
37     int head[N],next[M],cnt;
38     void ins(int x,int y,int z,int c){
39         E[++cnt]=(edge){x,y,z,c};
40         next[cnt]=head[x]; head[x]=cnt;
41     }
42     void add(int x,int y,int z,int c){
43         ins(x,y,z,c); ins(y,x,0,-c);
44     }
45     int from[N],Q[M],d[N],S,T;
46     bool inq[N];
47     bool spfa(){
48         int l=0,r=-1;
49         F(i,1,T) d[i]=INF;
50         d[S]=0; Q[++r]=S; inq[S]=1;
51         while(l<=r){
52             int x=Q[l++]; inq[x]=0;
53             for(int i=head[x];i;i=next[i])
54                 if(E[i].v && d[x]+E[i].c<d[E[i].to]){
55                     d[E[i].to]=d[x]+E[i].c;
56                     from[E[i].to]=i;
57                     if(!inq[E[i].to]){
58                         Q[++r]=E[i].to;
59                         inq[E[i].to]=1;
60                     }
61                 }
62         }
63         return d[T]!=INF;
64     }
65     void mcf(){
66         int x=INF;
67         for(int i=from[T];i;i=from[E[i].from])
68             x=min(x,E[i].v);
69         for(int i=from[T];i;i=from[E[i].from]){
70             E[i].v-=x;
71             E[i^1].v+=x;
72         }
73         ans+=x*d[T];
74     }
75     void init(){
76         n=getint(); m=getint(); size=getint();
77         cnt=1; S=0; T=n+1;
78         int x;
79         F(i,1,n){
80             x=getint();
81             add(i,T,x,0);
82         }
83         F(i,1,n){
84             x=getint();
85             add(S,i,INF,x);
86             if (i<n) add(i,i+1,size,m);
87         }
88         while(spfa()) mcf();
89         printf("%d\n",ans);
90     }
91 }G1;
92 int main(){
93 #ifndef ONLINE_JUDGE
94     freopen("input.txt","r",stdin);
95 //  freopen("output.txt","w",stdout);
96 #endif
97     G1.init();
98     return 0;
99 }