hdu 1114 完全背包

完全背包化为多重背包,时间为:250ms

#include<iostream>#include<cstdio>#include<cmath>using namespace std;int num[500];int w[500],p[500];int n;int dp[10000];int min(int a,int b){return a>b?b:a;}void solve(int sum,int weight,int value){for(int i=sum;i>=weight;i--)dp[i]=min(dp[i],dp[i-weight]+value);}int main(){int t;scanf("%d",&t);while(t--){int e,f,m;scanf("%d%d",&e,&f);m=f-e;int i,k;scanf("%d",&n);for(i=0;i<n;i++)scanf("%d%d",&p[i],&w[i]);for(i=0;i<=m;i++)dp[i]=100000000;dp[0]=0;for(i=0;i<n;i++)num[i]=(int)ceil(double(m)/(double)w[i]);for(i=0;i<n;i++){k=1;while(k<num[i]){solve(m,k*w[i],k*p[i]);num[i]-=k;k<<=1;}solve(m,k*w[i],k*p[i]);}if(dp[m]!=100000000)printf("The minimum amount of money in the piggy-bank is %d./n",dp[m]);elseprintf("This is impossible./n");}return 0;} 

 

用完全背包做:109ms,神啊...

#include<iostream>#include<cstdio>#include<cmath>using namespace std;int num[500];int w[500],p[500];int n;int dp[10000];int min(int a,int b){return a>b?b:a;}void solve(int sum,int weight,int value){for(int i=weight;i<=sum;i++)dp[i]=min(dp[i],dp[i-weight]+value);}int main(){int t;scanf("%d",&t);while(t--){int e,f,m;scanf("%d%d",&e,&f);m=f-e;int i,k;scanf("%d",&n);for(i=0;i<n;i++)scanf("%d%d",&p[i],&w[i]);for(i=0;i<=m;i++)dp[i]=100000000;dp[0]=0;for(i=0;i<n;i++)num[i]=(int)ceil(double(m)/(double)w[i]);for(i=0;i<n;i++)solve(m,w[i],p[i]);if(dp[m]!=100000000)printf("The minimum amount of money in the piggy-bank is %d./n",dp[m]);elseprintf("This is impossible./n");}return 0;}