hdu 1171 多重背包
题意：给出价值和数量，求能分开的最近的两个总价值，例如10,20*2,30，分开就是40，40
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1 #include<cstdio> 2 #include<iostream> 3 #include<algorithm> 4 #include<cstring> 5 #include<cmath> 6 #include<queue> 7 #include<map> 8 using namespace std; 9 #define MOD 1000000007 10 const int INF=0x3f3f3f3f; 11 const double eps=1e-5; 12 typedef long long ll; 13 #define cl(a) memset(a,0,sizeof(a)) 14 #define ts printf("*****\n"); 15 const int MAXN=250010; 16 int n,m,tt; 17 int a[MAXN],b[MAXN]; 18 int dp[MAXN]; 19 20 int nValue; 21 //0-1背包，代价为cost,获得的价值为weight 22 void ZeroOnePack(int cost,int weight) 23 { 24 for(int i=nValue;i>=cost;i--) 25 dp[i]=max(dp[i],dp[i-cost]+weight); 26 } 27 //完全背包，代价为cost,获得的价值为weight 28 void CompletePack(int cost,int weight) 29 { 30 for(int i=cost;i<=nValue;i++) 31 dp[i]=max(dp[i],dp[i-cost]+weight); 32 } 33 //多重背包 34 void MultiplePack(int cost,int weight,int amount) 35 { 36 if(cost*amount>=nValue)CompletePack(cost,weight); 37 else 38 { 39 int k=1; 40 while(k<amount) 41 { 42 ZeroOnePack(k*cost,k*weight); 43 amount-=k; 44 k<<=1; 45 } 46 ZeroOnePack(amount*cost,amount*weight); 47 } 48 } 49 int main() 50 { 51 int i,j,k; 52 #ifndef ONLINE_JUDGE 53 freopen("1.in","r",stdin); 54 #endif 55 while(scanf("%d",&n)!=EOF) 56 { 57 if(n<0) break; 58 nValue=0; 59 for(i=0;i<n;i++) 60 { 61 scanf("%d%d",&a[i],&b[i]); 62 nValue+=a[i]*b[i]; 63 } 64 cl(dp); 65 for(i=0;i<n;i++) 66 { 67 MultiplePack(a[i],a[i],b[i]); 68 } 69 int v=nValue/2; 70 while(dp[v]!=v) v--; 71 printf("%d %d\n",nValue-v,v); 72 } 73 }
