UVA 116——Unidirectional TSP（字典序输出）

原题链接

思路

代码

#pragma GCC optimize(2)
#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<ll, ll>PLL;
typedef pair<int, int>PII;
typedef pair<double, double>PDD;
#define I_int ll
inline ll read()
{
    ll x = 0, f = 1;
    char ch = getchar();
    while(ch < '0' || ch > '9')
    {
        if(ch == '-')f = -1;
        ch = getchar();
    }
    while(ch >= '0' && ch <= '9')
    {
        x = x * 10 + ch - '0';
        ch = getchar();
    }
    return x * f;
}
#define read read()
#define closeSync ios::sync_with_stdio(0);cin.tie(0);cout.tie(0)
#define multiCase int T;cin>>T;for(int t=1;t<=T;t++)
#define rep(i,a,b) for(int i=(a);i<=(b);i++)
#define repp(i,a,b) for(int i=(a);i<(b);i++)
#define per(i,a,b) for(int i=(a);i>=(b);i--)
#define perr(i,a,b) for(int i=(a);i>(b);i--)
ll ksm(ll a, ll b, ll p)
{
    ll res = 1;
    while(b)
    {
        if(b & 1)res = res * a % p;
        a = a * a % p;
        b >>= 1;
    }
    return res;
}
const int inf = 0x3f3f3f3f;
#define PI acos(-1)

const int maxn =210;

int n,m,mp[maxn][maxn];
int dp[maxn][maxn],path[maxn][maxn];
int main()
{
    while(scanf("%d%d",&n,&m)!=EOF)
    {
        for(int i=1; i<=n; i++)
            for(int j=1; j<=m; j++)
                mp[i][j]=read;
        memset(dp,0x3f,sizeof dp);
        memset(path,0,sizeof path);
        for(int j=m;j;j--){
            for(int i=1;i<=n;i++){
                if(j==m) dp[i][j]=mp[i][j];
                else{
                    int a[3]={i,i+1,i-1};
                    if(i==1) a[2]=n;
                    if(i==n) a[1]=1;
                    sort(a,a+3);
                    for(int k=0;k<3;k++){
                        int t=dp[a[k]][j+1]+mp[i][j];
                        if(t<dp[i][j]){
                            dp[i][j]=t;
                            path[i][j]=a[k];
                        }
                    }
                }
            }
        }
        int res=inf,pos;
        for(int i=1; i<=n; i++)
            if(dp[i][1]<res){
                res=dp[i][1];pos=i;
            }
        printf("%d",pos);
        for(int i=path[pos][1],j=2;j<=m;i=path[i][j],j++)
            printf(" %d",i);
        puts("");
        printf("%d
",res);
    }
    return 0;
}