48 lines
915 B
C++
48 lines
915 B
C++
#include <cstdio>
|
|
#include <cstdlib>
|
|
#include <cstring>
|
|
#include <algorithm>
|
|
using namespace std;
|
|
|
|
/// 0-1背包问题(一维数组空间优化)
|
|
|
|
namespace Package1_SpaceOptimized
|
|
{
|
|
const int MAXM = 30000 + 5;
|
|
const int MAXN = 25 + 5;
|
|
int ldp[MAXM];
|
|
int w[MAXN];
|
|
int v[MAXN];
|
|
int N,M;
|
|
void solve()
|
|
{
|
|
for(int i=1;i<=N;i++)
|
|
{
|
|
for(int j=M;j>=1;j--)///从M到1逆序循环
|
|
{
|
|
int a=ldp[j];
|
|
int b=-1;
|
|
if(j-w[i]>=0) b=ldp[j-w[i]]+v[i];
|
|
ldp[j]=max(a,b);
|
|
}
|
|
}
|
|
printf("%d\n",ldp[M]);
|
|
}
|
|
int main()
|
|
{
|
|
scanf("%d %d",&M,&N);
|
|
for(int i=1;i<=N;i++)
|
|
{
|
|
scanf("%d %d",&w[i],&v[i]);
|
|
v[i]=w[i]*v[i];
|
|
}
|
|
solve();
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
int main()
|
|
{
|
|
return Package1_SpaceOptimized::main();
|
|
}
|