#include <bits/stdc++.h> #define int long long using namespace std; int md[100005]; signed main() { freopen("c.in", "r", stdin); freopen("c.out", "w", stdout); int n, d; scanf("%lld %lld", &n, &d); int tot = 0; for (int i = 1; i <= n; i++) { int x; scanf("%lld", &x); tot += x; md[i % d] += x; } int ans = 0; for (int i = 0; i < d; i++) { ans = max(ans, md[i]); } printf("%lld", tot - ans); return 0; }