HDU 2191 【多重背包】
Input
输入数据首先包含一个正整数C,表示有C组测试用例,每组测试用例的第一行是两个整数n和m(1<=n<=100, 1<=m<=100),分别表示经费的金额和大米的种类,然后是m行数据,每行包含3个数p,h和c(1<=p<=20,1<=h<=200,1<=c<=20),分别表示每袋的价格、每袋的重量以及对应种类大米的袋数。
Output
对于每组测试数据,请输出能够购买大米的最多重量,你可以假设经费买不光所有的大米,并且经费你可以不用完。每个实例的输出占一行。
Sample Input
1
8 2
2 100 4
4 100 2
Sample Output
400
【分析】:
【代码】:
#include<cstdio>
#include<string>
#include<cstdlib>
#include<cmath>
#include<iostream>
#include<cstring>
#include<set>
#include<queue>
#include<algorithm>
#include<vector>
#include<map>
#include<cctype>
#include<stack>
#include<sstream>
#include<list>
#include<assert.h>
#include<bitset>
#include<numeric>
#define debug() puts("++++")
#define gcd(a,b) __gcd(a,b)
#define lson l,m,rt<<1
#define rson m+1,r,rt<<1|1
#define fi first
#define se second
#define pb push_back
#define sqr(x) ((x)*(x))
#define ms(a,b) memset(a,b,sizeof(a))
#define sz size()
#define be begin()
#define pu push_up
#define pd push_down
#define cl clear()
#define lowbit(x) -x&x
#define all 1,n,1
#define rep(i,n,x) for(int i=(x); i<(n); i++)
#define in freopen("in.in","r",stdin)
#define out freopen("out.out","w",stdout)
using namespace std;
typedef long long LL;
typedef unsigned long long ULL;
typedef pair<int,int> P;
const int INF = 0x3f3f3f3f;
const LL LNF = 1e18;
const int MAXN = 1e3 + 5;
const int maxm = 1e6 + 10;
const double PI = acos(-1.0);
const double eps = 1e-8;
const int dx[] = {-1,1,0,0,1,1,-1,-1};
const int dy[] = {0,0,1,-1,1,-1,1,-1};
const int mon[] = {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
const int monn[] = {0, 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
int n,m,k;
int num[maxm];
int v[maxm], w[maxm],dp[maxm];
int main()
{
int t;
cin>>t;
while(t--)
{
ms(dp,0);
cin>>m>>n;
for(int i=0;i<n;i++){
cin>>w[i]>>v[i]>>num[i];
}
for(int i=0;i<n;i++){
for(int k=1; k<=num[i]; k++){
for(int j=m; j>=w[i]; j--){
dp[j]=max(dp[j],dp[j-w[i]]+v[i]);
}
}
}
cout<<dp[m]<<endl;
}
return 0;
}
/*
1
8 2
2 100 4
4 100 2
Sample Output
400
*/
【二进制优化】:
#include<cstdio>
#include<string>
#include<cstdlib>
#include<cmath>
#include<iostream>
#include<cstring>
#include<set>
#include<queue>
#include<algorithm>
#include<vector>
#include<map>
#include<cctype>
#include<stack>
#include<sstream>
#include<list>
#include<assert.h>
#include<bitset>
#include<numeric>
#define debug() puts("++++")
#define gcd(a,b) __gcd(a,b)
#define lson l,m,rt<<1
#define rson m+1,r,rt<<1|1
#define fi first
#define se second
#define pb push_back
#define sqr(x) ((x)*(x))
#define ms(a,b) memset(a,b,sizeof(a))
#define sz size()
#define be begin()
#define pu push_up
#define pd push_down
#define cl clear()
#define lowbit(x) -x&x
#define all 1,n,1
#define rep(i,n,x) for(int i=(x); i<(n); i++)
#define in freopen("in.in","r",stdin)
#define out freopen("out.out","w",stdout)
using namespace std;
typedef long long LL;
typedef unsigned long long ULL;
typedef pair<int,int> P;
const int INF = 0x3f3f3f3f;
const LL LNF = 1e18;
const int MAXN = 1e3 + 5;
const int maxm = 1e6 + 10;
const double PI = acos(-1.0);
const double eps = 1e-8;
const int dx[] = {-1,1,0,0,1,1,-1,-1};
const int dy[] = {0,0,1,-1,1,-1,1,-1};
const int mon[] = {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
const int monn[] = {0, 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
int n,m,k;
int num[maxm];
int v[maxm], w[maxm],dp[maxm];
void zero(int cost ,int value)
{
for(int j=m;j>=cost;j--){
dp[j]=max(dp[j],dp[j-cost]+value);
}
}
void cmp(int cost, int value)
{
for(int j=cost;j<=m;j++){
dp[j]=max(dp[j],dp[j-cost]+value);
}
}
void mul(int cost, int value,int cnt)
{
if(m<=cnt*cost) {
cmp(cost,value);
return ;
}
else{
int k=1;
while(k<=cnt){
zero(k*cost,k*value);
cnt-=k;
k<<=1;
}
}
zero(cnt*cost,cnt*value);
}
int main()
{
int t;
cin>>t;
while(t--)
{
ms(dp,0);
cin>>m>>n;
for(int i=1;i<=n;i++){
cin>>w[i]>>v[i]>>num[i];
}
for(int i=1;i<=n;i++){
mul(w[i],v[i],num[i]);
}
cout<<dp[m]<<endl;
}
return 0;
}
/*
1
8 2
2 100 4
4 100 2
400
*/