URAL1029. Ministry（DP+路径）

链接

路径麻烦啊 很多细节 倒回去搜一遍

卡了一节数据库。。

  1 #include <iostream>

  2 #include<cstdio>

  3 #include<cstring>

  4 #include<algorithm>

  5 #include<stdlib.h>

  6 using namespace std;

  7 #define LL long long

  8 int u,o,path[50010],flag;

  9 LL sum[110][510],dp[110][510],f[110][510];

 10 int m,n;

 11 void dfs(int u,int v)

 12 {

 13     if(flag)

 14     return ;

 15     int i,j,tt=o;

 16     if(v==1)

 17     {

 18         o++;

 19         path[o] = u;

 20         for(i = o ; i > 1 ; i--)

 21         printf("%d ",path[i]);

 22         printf("%d\n",path[1]);

 23         flag = 1;

 24         return ;

 25     }

 26     if(dp[v][u]==dp[v-1][u]+f[v][u])

 27     {

 28         o = tt;

 29         path[++o] = u;

 30         dfs(u,v-1);

 31     }

 32     for(i = u-1; i >= 1 ; i--)

 33     {

 34         if(dp[v][i]!=dp[v-1][i]+f[v][i])

 35         continue;

 36         o = tt;

 37         if(dp[v][u]==dp[v][i]+sum[v][u]-sum[v][i])

 38         {

 39             for(j = u ; j>= i ; j--)

 40             path[++o] = j;

 41             dfs(i,v-1);

 42         }

 43     }

 44     for(i = u+1 ; i <= m ; i++)

 45     {

 46         if(dp[v][i]!=dp[v-1][i]+f[v][i])

 47         continue;

 48         o = tt;

 49         if(dp[v][u]==dp[v][i]+sum[v][i-1]-sum[v][u-1])

 50         {

 51             for(j = u; j <= i; j++)

 52             path[++o] = j;

 53             dfs(i,v-1);

 54         }

 55     }

 56     o = tt;

 57 }

 58 int main()

 59 {

 60     int i,j,g;

 61     flag=0;

 62     scanf("%d%d",&n,&m);

 63     for(i = 1; i <= n ;i++)

 64     {

 65         for(j = 1; j <=m ; j++)

 66         {

 67             scanf("%lld",&f[i][j]);

 68             sum[i][j] = sum[i][j-1]+f[i][j];

 69         }

 70     }

 71     for(i = 1 ;i <= n ;i++)

 72     {

 73         for(j = 1; j <=m ; j++)

 74         dp[i][j] = dp[i-1][j]+f[i][j];

 75         for(j = 1; j <= m ; j++)

 76         {

 77             for(g = 1; g < j ;g++)

 78             dp[i][j] = min(dp[i][j],dp[i][g]+sum[i][j]-sum[i][g]);

 79             for(g = j+1 ; g <=m ; g++)

 80             dp[i][j] = min(dp[i][j],dp[i][g]+sum[i][g-1]-sum[i][j-1]);

 81         }

 82     }

 83     LL ans = dp[n][1],u = 1;

 84     for(i = 1; i <= m ; i++)

 85     {

 86         if(ans>=dp[n][i])

 87         {

 88             ans = dp[n][i];

 89             if(dp[n][i]==dp[n-1][i]+f[n][i])

 90             u = i;

 91         }

 92     }

 93     o++;

 94     path[o] = u;

 95     if(n==1)

 96     printf("%d\n",u);

 97     else

 98     dfs(u,n-1);

 99     return 0;

100 }

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