这题数据规模并不大!!这是重点………

  所以直接暴力DP就好了:f[i]表示前 i 天的最小花费,则有$f[i]=min\{f[j]+cost[j+1][i]+k\} (0\leq j \leq i-1)$其中cost数组表示第L天到第R天只用一种运输方案连续运$R-L+1$天的最小代价,因为n很小所以暴力枚举L、R,用最短路算法来算……

  记得开long long

 1 /**************************************************************
 2     Problem: 1003
 3     User: Tunix
 4     Language: C++
 5     Result: Accepted
 6     Time:52 ms
 7     Memory:1396 kb
 8 ****************************************************************/
 9  
10 //BZOJ 1003
11 #include<vector>
12 #include<cstdio>
13 #include<cstring>
14 #include<cstdlib>
15 #include<iostream>
16 #include<algorithm>
17 #define rep(i,n) for(int i=0;i<n;++i)
18 #define F(i,j,n) for(int i=j;i<=n;++i)
19 #define D(i,j,n) for(int i=j;i>=n;--i)
20 #define pb push_back
21 using namespace std;
22 inline int getint(){
23     int v=0,sign=1; char ch=getchar();
24     while(ch<'0'||ch>'9'){ if (ch=='-') sign=-1; ch=getchar();}
25     while(ch>='0'&&ch<='9'){ v=v*10+ch-'0'; ch=getchar();}
26     return v*sign;
27 }
28 const int N=110,M=1000,INF=100000000;
29 typedef long long LL;
30 /******************tamplate*********************/
31 int to[M],next[M],head[N],len[M],cnt;
32 void ins(int x,int y,int z){
33     to[++cnt]=y; next[cnt]=head[x]; head[x]=cnt; len[cnt]=z;
34 }
35 void add(int x,int y,int z){
36     ins(x,y,z);ins(y,x,z);
37 }
38 /*******************edge************************/
39 int n,m,k,e;
40 LL f[N],cost[N][N],d[N];
41 int Q[M];
42 bool can[N][N],vis[N],inq[N];
43 LL spfa(){
44     int l=0,r=-1;
45     F(i,2,m) d[i]=INF;
46     d[1]=0;inq[1]=1;
47     Q[++r]=1;
48     while(l<=r){
49         int x=Q[l++];
50         inq[x]=0;
51         for(int i=head[x];i;i=next[i])
52             if(vis[to[i]] && d[to[i]]>d[x]+len[i]){
53                 d[to[i]]=d[x]+len[i];
54                 if(!inq[to[i]]){
55                     Q[++r]=to[i];
56                     inq[to[i]]=1;
57                 }
58             }
59     }
60     return d[m];
61 }
62  
63 int main(){
64 #ifndef ONLINE_JUDGE
65     freopen("1003.in","r",stdin);
66     freopen("1003.out","w",stdout);
67 #endif
68     n=getint(); m=getint(); k=getint(); e=getint();
69     int x,y,z;
70     F(i,1,e){
71         x=getint(); y=getint(); z=getint();
72         add(x,y,z);
73     }
74     int q=getint();
75     F(i,1,m) F(j,1,n) can[i][j]=1;
76     F(i,1,q){
77         x=getint(); y=getint(); z=getint();
78         F(j,y,z) can[x][j]=0;
79     }
80     F(i,1,n) F(j,i,n){
81         F(x,1,m) vis[x]=1;
82         F(x,2,m-1) F(k,i,j) if(!can[x][k]) vis[x]=0;
83         cost[i][j]=spfa()*(j-i+1);
84     }
85     F(i,1,n) f[i]=cost[1][i];
86     F(i,1,n) F(j,0,i-1) f[i]=min(f[i],f[j]+cost[j+1][i]+k);
87     printf("%lld\n",f[n]);
88     return 0;
89 }
90 
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