HDU3535分组背包

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首先这个是我参考别人的思路后写出来的，一开始误以为是混合背包，

#include<iostream>#include<cstdio>#include<algorithm>#include<cstring>#include<string>#include<vector>#include<queue>#include<cmath>#include<memory.h>using namespace std;int dp[102][102];void clear(){memset(dp,0,sizeof(dp));}int main(){int n,t;int m,type;int c,g;while(cin>>n>>t){clear();for(int i=1;i<=n;i++){scanf("%d %d",&m,&type);if(type==0)for(int l=0;l<=t;l++)dp[i][l]=-1;//不选就为-1elsefor(int l=0;l<=t;l++)dp[i][l]=dp[i-1][l];//传递背包的值for(int j=1;j<=m;j++){scanf("%d %d",&c,&g);for(int k=t;k>=c;k--){if(type==0)//必须一种，传递关系中不能有 （向下传且出现不选）的现象{if(dp[i][k-c]!=-1)dp[i][k]=max(dp[i][k],dp[i][k-c]+g);if(dp[i-1][k-c]!=-1)dp[i][k]=max(dp[i][k],dp[i-1][k-c]+g);}if(type==1)//至多一种，传递关系中不能有（有随意选并且有随意选）的现象{if(dp[i-1][k]!=-1)dp[i][k]=max(dp[i][k],dp[i-1][k]);if(dp[i-1][k-c]!=-1)dp[i][k]=max(dp[i][k],dp[i-1][k-c]+g);}if(type==2)//随意{if(dp[i-1][k]!=-1)dp[i][k]=max(dp[i][k],dp[i-1][k]);if(dp[i][k-c]!=-1)dp[i][k]=max(dp[i][k],dp[i][k-c]+g);if(dp[i-1][k-c]!=-1)dp[i][k]=max(dp[i][k],dp[i-1][k-c]+g);}}}}cout<<dp[n][t]<<endl;}}

接下来这个是我参考思路的那个代码，自认为大神的代码比我的好理解多了

#include<iostream>  #include<cstdio>  #include<algorithm>  #include<memory.h>  using namespace std;  int dp[125][125],n,m;  struct node  {      int sum;      int Typ;      int c[125];      int g[125];  } p[125];  int main()  {      //int i,j,t,k;      while(scanf("%d%d",&n,&m)==2)      {          memset(dp,-1,sizeof(dp));          memset(dp[0],0,sizeof(dp[0]));          for(int i=1; i<=n; i++)          {              cin>>p[i].sum>>p[i].Typ;              for(int j=1; j<=p[i].sum; j++)              {                  cin>>p[i].c[j]>>p[i].g[j];              }          }          for( int i = 1 ; i <= n ; i ++ )          {              if(p[i].Typ==0)              {                  for( int j = 1 ; j<=p[i].sum; j++ )                      for( int k = m ; k >= p[i].c[j] ; k-- )                      {                          if( dp[i][k-p[i].c[j]]!=-1 )                              dp[i][k] = max(dp[i][k],dp[i][k-p[i].c[j]]+p[i].g[j]);                          if( dp[i-1][k-p[i].c[j]]!=-1 )                              dp[i][k] = max(dp[i][k],dp[i-1][k-p[i].c[j]]+p[i].g[j]);                      }                }              if(p[i].Typ==1)              {                  for(int j=0;j<=m;j++) dp[i][j] = max(dp[i-1][j],dp[i][j]);                  for( int j = 1 ; j <= p[i].sum; j++ )                      for( int k = m ; k >= p[i].c[j]; k-- )                      {                          if(dp[i-1][k-p[i].c[j]] != -1 )                              dp[i][k] = max(dp[i][k],dp[i-1][k-p[i].c[j]]+p[i].g[j]);                      }                }              if(p[i].Typ==2)              {                  for( int j = 0 ; j <= m ; j++)                  {                      dp[i][j] = dp[i-1][j];                  }                  for( int j = 1 ; j <=p[i].sum; j++ )                      for( int k = m ; k >= p[i].c[j] ; k-- )                      {                          if(dp[i-1][k-p[i].c[j]] != -1 )                              dp[i][k] = max(dp[i][k],dp[i][k-p[i].c[j]]+p[i].g[j]);                      }              }          }          cout<<dp[n][m]<<endl;      }      return 0;  }