【UVA116】 单向TSP Unidirectional TSP [动态规划]

 1 #include<iostream>
 2 #include<cstdio>
 3 #include<queue>
 4 #include<cstring>
 5 #include<cmath>
 6 #include<stack>
 7 #include<algorithm>
 8 using namespace std;
 9 #define ll long long
10 #define rg register
11 const int N=100+5,M=20,inf=0x3f3f3f3f;
12 int n,m,a[M][N],f[M][N],nxt[M][N],ans,fir;
13 template <class t>void rd(t &x)
14 {
15     x=0;int w=0;char ch=0;
16     while(!isdigit(ch)) w|=ch==‘-‘,ch=getchar();
17     while(isdigit(ch)) x=(x<<1)+(x<<3)+(ch^48),ch=getchar();
18     x=w?-x:x;
19 }
20 
21 int main()
22 {
23     //freopen("in.txt","r",stdin);
24     //freopen("nocows.out","w",stdout);
25     while(scanf("%d%d",&m,&n)==2)//m行n列 
26     {
27         memset(a,0,sizeof(a));
28         memset(nxt,0,sizeof(nxt));
29         ans=inf;
30         for(rg int i=1;i<=m;++i)
31         for(rg int j=1;j<=n;++j) rd(a[i][j]);
32         for(rg int j=n;j>0;--j)//列 
33         for(rg int i=1;i<=m;++i)//行 
34         {
35             if(j==n) f[i][j]=a[i][j];
36             else{
37                 int row[3]={i,(i-1+m)%m,(i+1)%m};
38                 if(!row[2]) row[2]=m;if(!row[1]) row[1]=m;
39                 sort(row,row+3);
40                 f[i][j]=inf;
41                 for(rg int k=0;k<3;++k)
42                 {
43                     int v=a[i][j]+f[row[k]][j+1];
44                     if(v<f[i][j]) f[i][j]=v,nxt[i][j]=row[k];
45                  } 
46             }
47             if(j==1&&f[i][j]<ans) ans=f[i][j],fir=i;
48         }
49         printf("%d",fir);
50         for(rg int i=nxt[fir][1],j=1;j<n;i=nxt[i][++j])
51         printf(" %d",i);
52         printf("\n%d\n",ans);
53     }
54     return 0;
55 }