#include using namespace std; #include

int main() { int n,k; cin>>n>>k;

vector<long long> happy;
happy.resize(n);
for(int i = 0;i<n;++i)
{
    cin>>happy[i];
}
vector<long long> shy;
shy.resize(n);
for(int i = 0;i<n;++i)
{
    cin>>shy[i];
}


int left = 0,right = 0;
long long sum1 = 0,sum2 = 0,maxs1 = 0,maxs2 = 0;
int eat = 0;
while(right<n)
{
    if(left + k > n)
    {
        break;
    }
    while(right - left + 1 < k)
    {
        ++right;
    }
    sum1 = 0;
    sum2 = 0;
    for(int i = left;i<=right;++i)
    {
        sum1 += happy[i];
        sum2 += shy[i];
    }
    if(sum1>maxs1 || (sum1 == maxs1 && sum2<maxs2))
    {
        maxs2 = sum2;
        maxs1 = sum1;
        eat = left + 1;
    }
    left++;
}
cout<<eat<<endl;
return 0;

}