20分，不知道错哪里了

#include <bits/stdc++.h>
using namespace std;
inline int read()
{
	int r=0,f=1;
	char c=getchar();
	while(c<'0'||c>'9')
	{
		if(c=='-')
		f=-1;
		c=getchar();
	}
	while(c>='0'&&c<='9')
	r=(r<<1)+(r<<3)+(c^'0'),c=getchar();
	return r*f;
}
int a[100005]={0};
int b[100005]={0};
int s[100005][2]={0};
int summ[100005][2]={0};
int main()
{
   int n=read(),m=read(),sum=0;
   for(int i=1;i<=n;++i)
   a[i]=read();
   for(int i=1;i<=n;++i)
   b[i]=read();
   for(int i=1;i<=n;++i)
   s[b[i]][i%2]++,summ[b[i]][i%2]=(summ[b[i]][i%2]+a[i])%10007;
   for(int i=1;i<=n;++i)
   sum=(sum+(i*(summ[b[i]][i%2]-a[i])+(s[b[i]][i%2]-1)*a[i]*i)%10007)%10007;
   cout<<sum%10007;
   return 0;
}