ans = 0
b = []
n, k = map(int,input().split())
a = sorted(list(map(int,input().split())), reverse=True)
for i in range(n):
if len(b)==k:
ans += (max(b)-1)*2
b = [a[i]]
else:
b.append(a[i])
ans += (max(b) - 1) * 2
print(ans)
#include <bits/stdc++.h>
using namespace std;
int n, k, a[2000], ans = 0;
int main()
{
ios_base::sync_with_stdio(false);
cin.tie(NULL);
cin >> n >> k;
for (int i = 0; i < n; i++)
{
cin >> a[i];
}
sort(a, a+n);
for (int i = n-1; i >= 0; i -= k)
{
int cnt = 0;
for (int j = 0; j < k && i - j >= 0; j++)
{
cnt = max(cnt, a[i - j]-1);
}
ans += cnt;
}
cout << ans*2;
return 0;
}1450A - Avoid Trygub | 327A - Flipping Game |
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