```cpp
#include <iostream>
#include <cstdio>
#include <algorithm>
using namespace std;
const int inf=100005;
int a[inf],b[inf];
int main(){
int n,m,cnt=0,ans=0;
scanf("%d%d",&m,&n);
for(register int i=1;i<=m;i++)
scanf("%d",&a[i]);
for(register int i=1;i<=n;i++)
scanf("%d",&b[i]);
sort(a+1,a+m+1);
sort(b+1,b+n+1);
for(register int i=1;i<=m;i++){
if(b[++cnt]==0){
cout<<0;return 0;
}
if(a[i]>=b[cnt]){
i--;ans+=b[cnt];
}
}
cout<<ans;
return 0;
}
```
by _RedForest @ 2018-12-27 17:43:18