#include<stdio.h>#include<string.h>#include<algorithm>#include<map>#include<string>using namespace std;struct NN{ int a,b;}nn[2100];int cmp(NN a,NN b){ return a.b<b.b;}int dp[300][300];int main(){ int t,n,m,i,j,k; int ans=0; scanf("%d",&t); while(t--) {ans=0;scanf("%d%d",&n,&m);for(i=1;i<=n;i++) scanf("%d",&nn[i].a);for(i=1;i<=n;i++) scanf("%d",&nn[i].b);sort(nn+1,nn+1+n,cmp);memset(dp,0,sizeof(dp));for(i=1;i<=n;i++){ for(j=1;j<=m;j++)dp[i][j]=max(dp[i-1][j],dp[i-1][j-1]+nn[i].a+nn[i].b*(j-1));}printf("%dn",dp[n][m]); }}
