#include <iostream>
#include <cstdio>
#include <cstring>
#include <cassert>
#define MAXN 100005
#define VAL(x) (x.first)
#define COLOR(x) (x.second)
using namespace std;

typedef long long int ll;
int N, Q, C[MAXN];
ll best[MAXN],V[MAXN], A, B, ans;
bool visit[MAXN];
pair<ll,int> t1,t2,cur;

////USE COUT FOR LONG LONG!!!
/*
  same A
  different B
  first B
*/
int main(){
 // freopen("C.in","r",stdin);
 // freopen("C.out","w",stdout);
  scanf("%d%d",&N, &Q);
  for(int i=1;i<=N;++i) cin >> V[i];
  for(int i=1;i<=N;++i) scanf("%d",&C[i]);
  for(int z=0;z<Q;++z){
    cin >> A >> B;
    if(A <= 0 && B <= 0){
      printf("0\n");
      continue;
    }
    //Init
    t1 = pair<ll,int>(0,0);
    t2 = pair<ll,int>(0,-1);
    ans = 0;
    memset(visit,0,sizeof(visit));

    for(int i=1;i<=N;++i){
      //Compute
      cur = pair<ll,int>(B * V[i],C[i]); //first
      //get different colour
      if(COLOR(t1) != COLOR(cur) && VAL(t1) > 0) VAL(cur) += VAL(t1);
      else if(COLOR(t2) != COLOR(cur) && VAL(t2) > 0) VAL(cur) += VAL(t2);
      //get same color
      if(visit[C[i]]) VAL(cur) = max(VAL(cur), best[C[i]] + A * V[i]);
      ans = max(ans,VAL(cur));
      //Update
      if(!visit[C[i]]) best[C[i]] = VAL(cur);
      else best[C[i]] = max(VAL(cur),best[C[i]]);
      visit[C[i]] = 1;
      //cur has different color from both t1 and t2
      if(COLOR(cur) != COLOR(t1) && COLOR(cur) != COLOR(t2)){
        if(VAL(cur) >= VAL(t1)){
          t2 = t1;
          t1 = cur;
        }
        else if(VAL(cur) > VAL(t2)) t2 = cur;
      }
      //cur has same color with EXACTLY one of them
      else{
        if(COLOR(cur) == COLOR(t1)) VAL(t1) = max(VAL(t1),VAL(cur));
        else VAL(t2) = max(VAL(t2),VAL(cur));
        if(VAL(t1) < VAL(t2)) swap(t1,t2);
      }
      assert(VAL(t1) >= VAL(t2));
      assert(COLOR(t1) != COLOR(t2));
    }
    cout << ans << endl;
  }
}